Tuesday brought another positive session for major U.S. indices, with the Dow Jones Industrial Average adding 0.16% to close at 48,442.41, the S&P 500 advancing 0.46% to 6,909.79, and the Nasdaq climbing 0.57% to 23,561.84. But for retail traders, the real action was in five individual names that captured attention for very different reasons.

Indaptus Therapeutics: Preferred Stock Deal Lights Up After-Hours

Indaptus Therapeutics Inc. (INDP) closed the regular session down 2.46% at $1.98, trading between an intraday high of $2.05 and a low of $1.92. The stock's 52-week range stretches from $47.60 down to $1.66, reflecting quite a journey. But the real fireworks came after the bell, when shares rocketed 64.65% to $3.26.

The catalyst? A securities purchase agreement filed with the SEC on December 22, 2025. Investor David E. Lazar bought 1 million shares of convertible preferred stock for $6.0 million in gross proceeds. The Series AA and Series AAA preferred shares can convert into a combined 111 million shares of common stock, subject to shareholder approval. The deal closed on December 23, 2025, and investors clearly liked what they saw.

UiPath: Moving Up to the MidCap 400

UiPath Inc. (PATH) had a rougher day during regular trading, falling 4.43% to close at $15.96. The stock traded between a high of $16.66 and a low of $15.68, within its 52-week range of $19.84 to $9.38. But like Indaptus, the after-hours session told a different story, with shares rising 6.8% to $17.05.

The news driving the attention: UiPath will join the S&P MidCap 400, replacing Synovus Financial Corp. (SNV). The change takes effect before the market opens on January 2, 2026. Index additions often bring buying pressure from funds that track those indices, which explains the enthusiasm in extended trading.

Trinity Biotech: HIV Testing Order Sparks Rally

Trinity Biotech plc (TRIB) delivered one of the day's most impressive moves, surging 43.50% to $1.28. The stock hit an intraday high of $1.75 and a low of $1.18, within a 52-week range of $3.44 to $0.48. Shares continued climbing in extended trading, adding another 4.7% to reach $1.34.

The company announced a significant HIV testing order alongside new balance-sheet restructuring efforts. Investors interpreted these developments as positive indicators of stabilizing demand and improved financial footing, providing much stronger revenue visibility going forward. For a company whose stock has been under pressure, that kind of clarity matters.

Sable Offshore: Pipeline Restart Gets Green Light

Sable Offshore Corp. (SOC) saw shares jump 36.32% to close at $10.36, trading between a high of $10.77 and a low of $7.90. The stock's 52-week range spans from $35 down to $3.72, showing significant volatility.

The catalyst was straightforward: the U.S. Pipeline and Hazardous Materials Safety Administration approved restart plans for the Las Flores Pipeline system. This approval followed a field inspection and discussions on safety procedures, marking a significant step forward for the company's operations. Getting regulatory approval to restart infrastructure is exactly the kind of concrete milestone that moves energy stocks.

McDonald's: Golden Arches Meet Golden Cross

McDonald's Corp. (MCD) had a quieter day, declining 1.70% to $310.84. The stock traded between a high of $314.12 and a low of $310.63, within its 52-week range of $326.32 to $276.53.

But the fast-food giant still drew attention for technical reasons. McDonald's, along with Coca-Cola (KO) and Yum Brands (YUM), recently experienced a Golden Cross—a technical pattern where a short-term moving average crosses above a long-term moving average. This pattern often signals a potential shift in long-term momentum, drawing attention to stability and pricing power. Technical traders watch these patterns closely because they can indicate sustained upward movement ahead.

The varied nature of Tuesday's movers—from biotech financing to pipeline approvals to technical patterns—shows how different catalysts can drive investor interest across sectors. Whether you're watching for regulatory approvals, index changes, or chart patterns, there's always something moving in the market.