Can Copying Congress’s Stock Trades Beat the Market?

Members of the US Congress can buy and sell individual stocks. The STOCK Act governing such purchases does not prohibit ordinary investing; it prohibits using material, non-public information obtained through public service for personal financial gain. It also requires disclosures that allow outsiders to track lawmakers’ transactions—and potentially copy them.

Some published back tests suggest that carefully selected congressional purchases can outperform the S&P 500 even in the period after public disclosure. However, it is important to note that the evidence supports selectivity, not blindly following every politician’s portfolio. Committee relevance and transaction size offer potential filters, although a specific “committee-linked trades above $100,000” strategy needs stronger verification than the available results provide.

The 45-Day Rule—With an Important Qualification

Under the STOCK Act reporting framework, members must disclose covered purchases, sales and exchanges exceeding $1,000, including transactions involving their spouses and dependent children. The deadline is the earlier of 30 days after learning of the transaction or 45 days after it occurred. Consequently, “within 45 days” is the outer limit, not a universal filing allowance.

These reports identify the asset, transaction date, transaction type and a dollar-value band—not the exact amount invested. A purchase reported in the $100,001–$250,000 category, for example, clearly exceeds $100,000 but leaves substantial uncertainty about its actual size.

For copy traders, the critical date is when that information becomes public. A back test that buys on the politician’s original transaction date gives followers information they did not yet possess, creating look-ahead bias. Disclosure-date testing addresses that basic problem.

What the Back Tests Show

Signal Congress publishes a disclosure-date analysis drawing on 34,027 congressional transactions collected across 2018–2026, with its reported 180-day excess-return measurement period covering 2023–2026. Its unfiltered purchase baseline underperformed, while several filtered groups did better.

Source: Signal Congress’s published back test.

These are separate strategy groups, not successive stages of one filtering process. Results represent average benchmark-relative outcomes, not annualized portfolio returns.

The strongest result involved buying patterns spanning both parties and both congressional chambers. Its benchmark-beating win rate was only 52%, however, illustrating a positive average advantage does not make each signal dependable.

Why Committee Links and Large Trades Matter

The committee hypothesis is more specific than simply following members who serve on committees: the relevant connection is between a committee’s jurisdiction and the company’s industry. Signal Congress incorporates that relationship into its scoring, assigning multipliers of 1.4 for members with direct sector oversight and 1.6 for committee chairs or ranking members. Those multipliers are model choices—not measured investment returns.

Transaction size supplies another possible conviction signal. The published large-purchase group improved on the unfiltered baseline but used a $50,000 midpoint threshold. It does not establish that raising the minimum to $100,000 improves performance further, nor isolate the incremental benefit of combining that threshold with committee relevance.

A $100,000 minimum is therefore a reasonable hypothesis to test, rather than a proven optimization. The available research supports investigating targeted filters but not claiming that this combination guarantees superior returns.

Read the Results Carefully

These findings come from a commercial research provider rather than an independently replicated academic study. Its research and methodology pages also describe different outlier-treatment rules, an inconsistency that warrants clarification before relying on the precise figures.

A convincing investable back test should additionally specify executable entry prices, portfolio sizing, overlapping positions, costs and out-of-sample performance. Historical simulations remain hypothetical and cannot capture every execution constraint. Congressional disclosures can supply research leads—but published excess returns are not promises of future profits.

Use as a Filter?

One way to utilise public information about Congressional stock holdings could be to use it as a filter to confirm stock trades. For example, if your strategy has you opening a position in stock A, and you see that a Congress member on a relevant committee just made a similar purchase, you might want to go overweight that stock.