This report aims to deeply analyze the U.S. equity options code “SST1G182500500.U,” particularly why its underlying stock code portion is displayed as “SST 1” instead of the original “SST” when sent to Interactive Brokers (IB). By analyzing the standardization structure of option symbols, related company behavior, and broker’s internal processing mechanisms, this report will elucidate the reasons behind this phenomenon and its impact on options traders.
U.S. Equity Options Symbol Standardization (OSI)
To ensure the efficient operation and transparency of the options market, the U.S. Option Clearing Corporation (OCC) has established a standardized options symbol system known as the Options Symbol Initiative (OSI). This system employs a unified alphanumeric format to clearly encode key information about the option contract 1. Since February 12, 2010, the 21-character OSI standard has been fully implemented in the United States and Canada, replacing the previous chaotic five-character code format 1.
A standard OSI options symbol typically contains the following four core components:
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Underlying Asset Code (Root Symbol): This is the code for the underlying stock or ETF that the option is based on. This field can contain up to six characters, and is usually the same as the trading code for the underlying stock. For example, the root symbol for Nike options is “NKE” 2. If the root symbol is less than six characters, it must be padded with spaces to reach a length of six characters 1.
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Expiration Date: This portion consists of six digits representing the expiration date in “year year-month month-day day (yymmdd)” format. For example, “220624” represents an option that expires on June 24, 2022 2.
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Call/Put Indicator: This is a single-character field indicating the type of option. ‘C’ represents a call option (Call Option), which grants the holder the right to purchase the underlying stock at a specified price; ‘P’ represents a put option (Put Option), which grants the holder the right to sell the underlying stock at a specified price 2.
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Strike Price: This is the preset price at which the option can be exercised to buy (call) or sell (put) the underlying stock. In the OSI format, the strike price is represented by eight digits, with the last three digits representing the decimal place (“mills,” hundredths of a dollar). To read the actual strike price, you must divide these eight digits by 1,000, or move the decimal point three places to the left. For example, “00099000” represents a strike price of $99.00 2.
Options, as derivatives, derive their value from the underlying asset. Most U.S. options are traded on exchanges such as the Chicago Board Options Exchange (CBOE) and cleared through the OCC. As the world’s largest equity derivative clearing organization, the OCC operates under the supervision of the SEC and CFTC to ensure the stability and integrity of the options market 2.
Parsing Option Code SST1G182500500.U
The option code “SST1G182500500.U” includes some elements of the OSI format, but also contains non-standard representations. This is often due to company-specific adjustments or broker internal display conventions.
SST1: Adjusted Underlying Code
“SST1” is the most important part of this option code, directly answering users’ core question about why the underlying code is “SST 1” rather than “SST.” The “1” suffix indicates that this option contract has undergone adjustments due to company actions (such as stock splits or mergers).
According to OCC’s official memorandum #56689, dated June 11, 2025, which clearly states: “Option symbol: SST changed to SST1,” effective date is June 12, 2025 3. This memo provides a clear explanation as to why the underlying symbol is “SST1.” Brokers like Robinhood have also confirmed this convention, stating that “if held option contracts on shares experience a reverse split…the stock code will be appended with a number. For example, if holding ABC options contracts, after a reverse split they will display as ABC1” 4. This industry standard further confirms the validity and purpose of the “SST1” suffix.
G1825: Expiration Date (Non-Standard Format)
The “G1825” portion differs significantly from the OSI standard’s “Year-Month-Day (yymmdd)” format (e.g., 2025 July 18 should be “250718”) 2. Prior to OSI implementation, option symbols were typically represented by single-letter codes for the month of expiration 5. In this older convention, the letter “G” represented the call option for July 5. If following this logic, “18” would represent the date, and “25” would represent the year. Therefore, “G1825” most likely represents July 18, 2025.
Despite the OSI standard’s explicit deprecation of this letter-code expiration date representation 1, “SST1” (a common OSI adjustment convention) persists alongside “G1825,” indicating that Interactive Brokers or its data sources may employ a hybrid or internal representation. This could be a legacy format for adjusting options, or a proprietary display convention used by the broker combining elements of the old symbol system with new adjustment indicators. The inconsistency in option symbols – the core OSI adjustment root symbol coexisting with a non-standard expiration date format – reflects the challenges in financial data standardization at the “last mile.” While central institutions strive for uniformity, brokers may introduce subtle variations or additional identifiers due to compatibility concerns, internal data management considerations, or platform functionality. This results in potential discrepancies between the “official” OSI symbol and the symbols a user might see or need to input on a specific trading platform. Therefore, options traders not only need to understand the general OSI standard but also must be aware of and adapt to any subtle differences in symbol representation employed by individual brokers.
00500: Strike Price
The “00500” provided by the user represents a five-digit number, which does not align with the eight-digit strike price field in the OSI standard [1]. If following OSI rules, dividing the eight digits by 1,000 would yield a strike price of $0.50 (as “00000500” equates to $0.50).
Considering that SST stock underwent a reverse split of 10 shares for every 1 share [9], strike prices are typically adjusted according to the split ratio (e.g., a $5.00 strike price would become $0.50 after a 1:10 split), making a very low strike price like $0.50 entirely reasonable for the adjusted options. The five digits “00500” likely represent the value 500, and when converted to “mills” (one-thousandth of a dollar), it equates to $0.50. The discrepancy in digit count may indicate that IB’s internal representation truncates leading zeros for very small strike prices before converting to the full 8-digit OSI format, or utilizes a different internal encoding.
.U: Broker-Specific Suffix
The “.U” suffix is not part of the standardized OCC/OSI 21 character format ¹. It is highly likely to be an internal identifier or marker used by Interactive Brokers (IB) or its specific market data vendors. Such suffixes are common in proprietary systems, used to convey additional information about contracts, such as their listed exchange, specific trading characteristics, or a unique identifier within their database.
Key Focus: SST1 Root Symbol
Despite potential minor deviations from the strict OSI specification for other option symbols, the “SST1” root symbol is undoubtedly the most critical element. It directly addresses the user’s core question and points to the company behavior that led to the symbol changes.
Company Behavior’s Impact: System1, Inc. (SST)’s Reverse Split
Corporate Actions’ Universal Impact on Option Contracts Adjustment
Options are financial derivatives whose value is directly derived from the underlying asset, such as stock [1]. Therefore, any significant event affecting the underlying security (typically referred to as corporate actions) must be reflected in the terms of open option contracts. This ensures that the economic value and integrity of the derivative remain intact [^13].
Corporate actions encompass a wide range of events, including stock splits (both forward and reverse), mergers, acquisitions, special dividends, and spin-offs [^13]. Each type of action can have a unique impact on option contracts.
Clearing Corporations (CCs) play a crucial role as the central clearinghouses for options in the United States. They are legally responsible for determining and implementing necessary adjustments to open option contracts in response to these corporate actions [^13]. These adjustments are formally communicated to market participants through detailed OCC Information Notices 3.
The method of adjustment varies depending on the corporate action, but may include changes to the option’s strike price, the number of shares (or other asset, referred to as the deliverable) represented by each contract, or even the option symbol itself. The overall objective of these adjustments is to preserve the total intrinsic value of the option contracts for option holders [^13].
Reverse Stock Splits and Their Typical Impact on Option Terms
A reverse stock split is a corporate action designed to reduce the number of outstanding shares while proportionally increasing the price per share6. For example, a 1-for-10 reverse split means that shareholders previously holding ten shares now own one share, but the value of the new share is theoretically ten times that of the old share6.
For options contracts, reverse splits typically require adjustments to contract terms. The OCC (Options Clearing Corporation) is responsible for determining the specific adjustment methods, which may involve changing the number of underlying shares represented by each option contract (e.g., in a 1:10 split, reducing from 100 shares to 10 shares) and/or proportionally increasing the strike price[^13]. The goal is to ensure that the total value represented by the contracts remains consistent with the value before the split.
Common results of reverse stock splits are changes in option symbols, typically adding a numerical suffix to the original stock code (e.g., “1”). This helps distinguish these adjusted contracts from newly issued standard options after the split3. A significant side effect is that these adjusted options often experience a substantial decline in liquidity[^13].
System1, Inc. (SST) 1-for-10 Reverse Stock Split Details
System1, Inc. (NYSE: SST) is a full-channel customer acquisition marketing platform that announced a 1-for-10 reverse stock split. This corporate action became effective prior to the market open on June 12, 2025 6.
The primary motivation for this reverse split was to increase the per-share trading price of its Class A common stock, allowing the company to regain compliance with New York Stock Exchange (NYSE) listing requirements 6.
As a direct result of this split, each 10 shares of common stock (including restricted and outstanding shares) automatically converted into 1 new share 7. This significantly reduced the total number of issued and outstanding Class A common shares from approximately 79.8 million to 7.98 million 7.
Despite the reverse split, the company’s Class A common stock continued to trade on the New York Stock Exchange using its existing trading code “SST”, but the CUSIP number was updated 7.
OCC’s Role in Determining and Implementing Adjustments: The Symbolic Change from SST to SST1
To address System1, Inc.’s reverse stock split, OCC issued memorandum #56689 on June 11, 2025, detailing the specific adjustments for options contracts 3.
The memo explicitly stated that, effective June 12, 2025, “Option Symbol: SST changed to SST1” 3. This official instruction from OCC was the direct cause of the “SST1” root symbol appearing in user option codes.
The memo further clarified the adjustment terms: “Contract Multiplier: 1. Strike Price Divider: 1. New Multiplier: 100 (e.g., for any dollar extension to premium or strike price, 1.00 would equal $100)” 3. This indicated that while the nominal contract multiplier remained at 100, the underlying asset referenced by the “SST1” symbol had been adjusted to reflect a split of 10 shares for every 1 reverse stock split, effectively maintaining the total contract value. The memo explicitly stated, “The price of SST1 will be determined as follows: SST1 = 0.10 (SST)” 3. This meant that each “SST1” option contract now represented 100 units, but each unit corresponded to 0.1 shares of the original SST stock, thereby preserving the total contract value after the split.
OCC Adjustments to SST Option Underlyings
For a 1-for-10 reverse stock split, OCC’s adjustments to existing SST options contracts aim to maintain the total economic value of the contracts. OCC did not change the number of shares per contract from 100 to 10 (which could occur in some split scenarios), but instead chose to adjust the underlying symbol itself to “SST1”.
This “SST1” symbol indicates that the option contract continues to represent 100 units, but each unit now corresponds to 0.1 shares of the original SST stock 3. Therefore, an “SST1” option contract effectively represents 100 * 0.1 = 10 shares after the 10-for-1 split. The strike price remains nominal in the symbol, but is now applied to this revalued underlying. This approach ensures that the total exercisable value of the contract remains consistent with its pre-split value. For example, if an option was exercised at a strike price of $50 before a 1:10 split, the exercise value would be $5,000 (100 shares * $50). After the split, the new issued post-split SST option strike price will be $500. However, the adjusted “SST1” option maintains its original strike price (e.g., $50) and applies it to a value of 1/10 of the underlying, effectively preserving the $5,000 total value [^13].
Table 1: Impact of SST Reverse Split on Option Contract Characteristics
| Underlying Stock Symbol | SST | SST (Applicable to New Shares and New Options) |
OCC Adjustment to the Deliverable of SST Options Contracts
Feature | Before 1-for-10 Reverse Split & 10-for-1 Split (Prior to June 12, 2025) | After 1-for-10 Reverse Split & 10-for-1 Split (Post June 12, 2025) |
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Adjusted Option Symbol | SST (Root symbol of the standard option) | SST1 (Root symbol of the existing, post-split option) |
OCC Adjustment to the Deliverable of SST Options Contracts
Feature | Before 1:10 Reverse Split (Prior to June 12, 2025) | After 1:10 Reverse Split (Post June 12, 2025) |
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Number of Shares Covered per Contract | 100 shares SST | 10 shares SST split (through 100 units of SST1) |
OCC Adjustment to SST Option Deliverable
Feature | Before Split-Reverse Split (Prior to June 12, 2025) | After Split-Reverse Split (Post June 12, 2025) |
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OCC Adjustment to SST Option Deliverable
Feature | Before 1-for-10 Reverse Split (Prior to June 12, 2025) | After 1-for-10 Reverse Split (Post June 12, 2025) |
---|---|---|
Underlying CUSIP | Original CUSIP | New CUSIP (87200P208) 10 |
OCC Adjustment to SST Option Deliverable
Feature | Before 1-for-10 Split and Reverse Split (Prior to June 12, 2025) | After 1-for-10 Split and Reverse Split (Post June 12, 2025) |
---|---|---|
Liquidity of Adjusted Options | Normal | Decreasing 13 |
OCC Adjustments to SST Option Deliverable Characteristics
Company actions, particularly reverse stock splits, while crucial for a company’s finances, often have “unforeseen” impacts on the derivatives market, introducing significant inefficiencies. The creation of unique “post-split options” – characterized by low liquidity, complex pricing and trading – fragments this security’s option market. This fragmentation reduces overall market efficiency and can lead to wider bid-ask spreads and difficulty in price discovery. This situation reflects a trade-off between corporate governance needs (such as stock splits to meet listing requirements) and the expectation of a fully liquid and simple derivatives market.
The Options Clearing Corporation (OCC) plays a critical role in this process. Company actions fundamentally alter the nature of the underlying security. Without intervention, this would create material discrepancies and potentially unfair outcomes within derivative contracts. The OCC utilizes its regulatory authority and clearing corporation functions to adjust option terms. This ensures that the economic value of the options is preserved and that the market remains orderly and fair. This ongoing adjustment mechanism is crucial for maintaining overall market integrity and ensuring continuity of value for option holders as the underlying company evolves.
Why Interactive Brokers Requires “SST 1”
Brokerage Handling of Adjustment Post-Expiration Option Symbols
Interactive Brokers (IB) as a leading brokerage firm, adheres explicitly to industry standards for option symbols. Their documentation confirms that IB “utilizes the 21-character ‘Options Symbol Initiative’ (OSI) format” 8. This commitment signifies their adherence to conventions established by Options Clearing Corporations (OCC) regarding the consolidation and processing of option symbols.
IB also provides clients with mechanisms to understand and view potential impacts on their holdings stemming from company actions. Their Trader Workstation (TWS) and Messaging Center offer tools for monitoring company behavior and its impact on positions [^15].
The practice of appending numerical suffixes (e.g., “1”) to original stock symbols to denote adjustment post-expiration is a common convention within the industry. This practice is often directly enforced by OCC to differentiate these contracts from newly issued, unadjusted underlying options related to company actions 3.
Other brokerages also follow similar practices. For example, Robinhood explicitly states “If your holding of stock options experiences a reverse split,…the stock code will be appended with a number. For example, if you hold ABC options, after a reverse split, it will display as ABC1” 4. Similarly, Merrill Edge notes that an “A” (representing “Adjusted”) will appear alongside the symbol and that the symbol itself “will include an additional digit – representing the adjustment” [^13]. Questrade also mentions “A” icons or other special indicators [^14].
“1” suffix as an industry convention for distinguishing contracts after adjustments
The symbol “SST1” is most directly and primarily due to official changes made by OCC. As detailed in OCC Information Memorandum #56689, following the 1-for-10 reverse stock split conducted by System1, Inc., the memorandum explicitly stated: “Option Symbol: SST changed to SST1” 3. This is not an internal naming convention of IB, but rather a standardized industry protocol for identifying options contracts post-adjustment.
This convention is crucial because new, unadjusted option series will be listed and begin trading on the underlying stock after reverse stock splits like those undertaken by companies. These new options will continue to use their original symbols (e.g., “SST”). To prevent confusion between these new standard contracts and older, adjusted contracts (where the underlying asset or effective exercise value relative to the post-split stock has been changed), adjusted contracts are assigned a modified symbol, such as “SST1” [^13].
Therefore, the “SST1” symbol is a clear identifier indicating that the terms of the option contract have been amended by OCC to reflect System1, Inc.’s 1-for-10 reverse stock split.
How does this convention maintain clarity in trading systems and prevent confusion?
Without this unique symbol system, traders might inadvertently trade a “SST” option, mistakenly believing it represents the standard contract for 100 shares post-split. In reality, it would be an older, adjusted contract, potentially representing a different number of shares (e.g., effectively representing 10 shares post-split SST) or having a revalued strike price.
Using adjusted symbols like “SST1” ensures that trading systems, clearinghouses, and all market participants can accurately identify, price, process, and settle these contracts. This precision is crucial in preventing errors in order routing, pricing, exercise, and assignment, which could otherwise lead to significant financial discrepancies and disputes.
Furthermore, this convention facilitates the simultaneous listing and trading of adjusted (legacy) options contracts and newly issued standard contracts on the same underlying security, with each contract identifiable by its unique symbol.
How Brokers Integrate These Adjusted Symbols into Their Platforms
Interactive Brokers, along with other brokers like Interactive Brokers, seamlessly integrates these OCC-mandated symbol changes into their trading platforms, including Trader Workstation (TWS). When corporate actions occur and the OCC publishes adjustments, IB updates the symbols for options contracts affected in client portfolios and option chains 8.
While the underlying stock itself continues to use its original symbol (“SST”) for trading, existing adjusted option positions will be displayed with their new symbol (“SST1”). For any order entry or queries related to these specific adjusted contracts, traders must use the “SST1” root symbol, which explains why users need to send “SST 1” to IB.
Here’s a key observation: The underlying stock, System1, Inc., continues to use its original symbol “SST” for trading 7. However, for existing, adjusted option contracts, the underlying root symbol within the option contract is “SST1” 3. This creates a subtle situation where when trading new options (these options will be based on the split-adjusted “SST” stock going public), the underlying is “SST”; but when trading existing, adjusted options, the underlying in the option symbol is “SST1”. This is a nuanced yet crucial distinction that can easily confuse traders.
This phenomenon highlights a significant operational complexity within option trading, extending beyond simply understanding OSI formats. It underscores the need for continuous vigilance and a deep understanding of how corporate actions fragment the options market. Simply knowing the current stock code isn’t enough; traders must differentiate between the standard option on the underlying asset and its adjusted counterpart with a changed symbol. This further emphasizes the importance of carefully reviewing option chain details, company action notifications, and broker-specific guidance.
The implementation of adjusted option symbols (such as “SST1”) is clearly an “operational necessity” for exchanges and brokers. It’s a powerful mechanism to manage the complexity of corporate actions, maintain market integrity, and ensure accurate clearing and settlement 1. However, from the end-user perspective, this change can be a significant source of confusion, as evidenced by direct user queries. While brokers attempt to mitigate this confusion through visual indicators like an “A” icon 13 or automatic adjustments within client portfolios 7, potential complexities remain.
This reveals the ongoing tension and trade-off between robust financial market infrastructure technical requirements and user-friendly interface demands. While the “SST1” convention is efficient and necessary from a systems perspective, it places an additional burden on individual traders to understand its implications. This highlights the enduring value of expert analysis and detailed educational reports in bridging this knowledge gap, ensuring that market participants can effectively and confidently navigate these complexities.
Impact on Traders & Best Practices
How to Identify Adjusted Options
- Symbol Suffixes: The most direct and immediate indicator of adjusted options is the numerical suffix appended to the option root symbol (e.g., “1”, “7” for mini options, or other numbers) 9. For example, seeing “SST1” instead of “SST” in an option held within System1, Inc. is a clear signal.
- Visual Indicators on Trading Platforms: Many well-known trading platforms, including Merrill Edge and Questrade, include specific visual cues. Traders should look for prominent “A” icons (representing “Adjusted”) or other special indicators alongside the option symbol in the option chain, quote window, or portfolio view [^13]. Interactive Brokers also uses icons (e.g., “C” representing company behavior) within its tax optimizer and messaging center to highlight affected positions [^15].
- Reduced Liquidity: A strong practical signal of an adjusted option is a significant decrease in trading volume and open interest compared to other options in the same series or newly issued, unlevered standard options based on the underlying asset [^13]. This activity reduction can lead to wider bid-ask spreads.
- Discrepant Strike Prices: Adjusted options may appear “out of whack” or inconsistent with other parts of the underlying stock option chain in terms of their strike prices [^13]. Furthermore, the presence of multiple put or call options with the same expiration date and strike price can indicate that an adjusted option is coexisting with newly issued standard options [^13].
- Pricing Anomalies: If an option’s price appears unusually low or “priced incorrectly” (or vice versa – “too good to be true”), investigation is warranted, as an adjustment may have altered its intrinsic value or the deliverable asset [^13].
The Importance of Reviewing OCC Information Memorandums and Broker Notices
The Options Clearing Corporation (OCC) is the final authority for determining and implementing adjustments to U.S. option contracts[^13]. Their “Information Memorandums” are the official and authoritative source for understanding the precise terms of any corporate action adjustment3. These memorandums provide key details regarding the deliverable (such as the number of shares per contract), strike prices, and changes in new option symbols.
Brokers such as Interactive Brokers have a legal obligation and operational capability to notify their clients of upcoming corporate actions that may impact their positions. These notices are typically available through client messaging centers, corporate action tools, or platform alerts[^15]. They provide information on how the broker will process adjustments within its systems.
Relying solely on visual cues or general understanding of corporate actions may be insufficient and can lead to costly misunderstandings. To ensure accurate position management and trading decisions, it is essential to review these official and broker-specific sources to determine the precise adjustment terms (such as cash in lieu of fractional shares, specific deliverable changes).
Post-Adjustment Option Considerations
- Significant Reduction in Liquidity: The most significant impact of post-adjustment options is a severe reduction in liquidity[^13]. This typically leads to wider bid-ask spreads, making it more difficult and costly to enter or exit positions at fair market prices. Traders may find it challenging to locate counterparties willing to transact at the desired order size.
- Increased Pricing Complexity: Due to changes in the deliverable asset, valuing post-adjustment options becomes more complex. Standard option pricing models (such as the Black-Scholes model) may not directly apply unless carefully manual adjustments are made to account for the new number of shares or effective exercise prices. This complexity can lead to inefficient pricing and increase trader risk.
- Restricted Trading Capacity: Certain brokerage platforms, such as Robinhood, may impose restrictions on trading post-adjustment options, typically limiting them to “only sell” positions4. This means traders can sell existing adjusted contracts but are prohibited from opening new positions, significantly restricting strategy flexibility.
- Ambiguity Regarding Exercise/Settlement: Understanding the exact deliverable asset at exercise or settlement is crucial. According to OCC’s specific adjustment terms, post-adjustment options may deliver a combination of shares, stock and cash, or even solely cash[^13]. Misunderstanding these terms can lead to unforeseen financial outcomes.
Recommendations for Options Traders
- Proactively Collect Information: Develop a habit of regularly monitoring financial news media and your broker’s corporate actions section to understand any announcements regarding the underlying stocks held in your options positions.
- Review Official Documentation: Immediately upon learning of company action, consult relevant OCC information memorandums (available on the OCC website or through your broker’s resources) as well as your broker’s specific notices. These are the authoritative sources for understanding precise adjustment terms.
- Reassess Your Strategy: Carefully evaluate how the adjustments affect the intrinsic value, breakeven points, and their role within your overall trading strategy for your specific option contracts. Determine if the adjusted contracts still align with your original investment thesis.
- Consider Position Management: Given the inherent complexity and typical liquidity constraints, it’s generally advisable to consider exiting positions if the adjustments render your options positions no longer aligned with your trading objectives or if liquidity issues become unmanageable.
- Monitor New Contracts: As a best practice, avoid establishing new positions in adjusted option contracts. Instead, focus on newly issued standard option series on the underlying stock following company action, as these options typically offer better liquidity and more direct pricing.
Company actions have an impact on derivative markets, which is an inherent part of corporate finance; however, they often introduce significant inefficiencies. The creation of adjustments to options, with their lower liquidity and more complex pricing and trading dynamics (such as liquidity and pricing behavior), fragment the option market for a particular security. This fragmentation reduces overall market efficiency and can lead to wider bid-ask spreads and difficulty in price discovery.
User queries perfectly illustrate that simply recognizing standard OSI format option symbols is insufficient when dealing with company actions. The seemingly minor “1” suffix (making it “SST1”) within the “SST” symbol – does not merely represent a superficial change; it foreshadows a series of fundamental changes to the contract terms, underlying asset, and market dynamics (such as liquidity, pricing behavior). This requires traders to go beyond simple symbol recognition and delve into the reasons behind these changes. This proactive research is an indispensable part of effective risk management and trading execution.
Conclusion
Option code “SST1G182500500.U” clearly indicates a tailored post-split option contract for System1, Inc. (SST). The key “SST1” root symbol was not arbitrarily assigned but is the direct result of an official adjustment enforced by the Options Clearing Corporation (OCC). This adjustment was necessary due to System1, Inc.’s 2025 June 12 effective one-for-ten reverse stock split.
This corporate action fundamentally altered the underlying deliverable of existing option contracts. While the nominal contract multiplier remains at 100, the “SST1” reference symbol now represents that each contract effectively corresponds to 10 shares of the post-split SST stock, thereby preserving the original economic value.
Interactive Brokers, like other major brokers, follows these OCC-enforced symbol conventions. By requiring the “SST1” (or “SST 1”) reference code, IB ensures accurate identification, processing, and display of these adjusted contracts within its trading systems, preventing potential errors and maintaining market integrity. The “G1825” and “.U” elements in user symbols may represent specific broker-defined or legacy expiration dates and internal identifiers, but they do not alter the fundamental reason for the “SST1” root symbol.
For any serious options trader, a thorough understanding of option symbols, particularly within this complex corporate context, is not just beneficial – it’s absolutely critical. Corporate actions can fundamentally change the terms, deliverable, and liquidity characteristics of outstanding option contracts, transforming them into “post-split option contracts” with unique symbols and trading behavior. Therefore, proactively monitoring company announcements, diligently reviewing official OCC information memoranda, and being acutely aware of broker-specific symbol conventions are essential best practices. These measures are crucial for accurately interpreting option contract terms, effectively managing risk exposures, and making informed strategic trading decisions in a dynamic market environment. Ignoring these key adjustments could lead to unforeseen financial consequences, operational complexities, and potentially significant losses.
Conclusion
Conclusion
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