Stocks making the biggest moves premarket: Reddit, Applied Materials, Sandisk, Wayfair & more

Reddit surged 12% after S&P Dow Jones said it will join the S&P 500 on Aug. 18. Applied Materials slid over 5% despite posting Q2 adjusted EPS of $3.50 on $9.12B revenue, with semiconductor systems revenue of $7.04B only slightly above the $6.96B FactSet consensus. In deal-driven moves, Workday gained ~2% after Reuters reported Silver Lake was in talks to buy it, and Fox added 2% after JPMorgan and Wells Fargo upgrades ahead of its $22B Roku acquisition. Overall, results/investor expectations and M&A headlines drove a mixed premarket tape.

Analysis

RDDT is a technical winner first and a fundamental story second: index inclusion creates forced buying and a near-term borrow squeeze, but that flow is finite. The risk is classic event drift — once passive demand is done, the stock can give back a meaningful slice unless earnings can justify the higher owner-quality multiple. The cleaner read-through is to watch who gets indexed out of the way; AVB faces mechanical selling, but the more actionable trade is often to fade the post-rebalance premium in the new entrant rather than chase it forever.

AMAT is telling us the market still wants an acceleration narrative from semi-capex, not just “good enough” execution. A modest beat inside a soft reaction usually means investors are marking down forward orders or margin leverage for the broader equipment group, which can spill over to KLAC/LRCX and the SMH/SOXX complex over the next 1-3 months. If capex commentary from foundry or memory customers does not improve, this is less a one-day miss than a multiple reset across the semi capital equipment stack.

The more interesting idiosyncratic setup is WDAY versus SNDK. WDAY has optionality from M&A, but after a sharp rerate the market is paying for certainty that may never arrive; without a formal process, upside is capped and vol crush risk is high. SNDK looks like the cleaner structural re-rate: if long-dated supply agreements really smooth earnings, the stock should trade less like a cyclical and more like a quality compounder, though that thesis needs proof in gross margin durability over the next few quarters.

Contrarian view: the market may be overemphasizing headline catalysts and underpricing durability. RDDT can be a sell-the-news after inclusion, while AMAT may be closer to a sector warning shot than a stock-specific miss; the falsifier is simple — stronger bookings/guidance from the next major semi spenders would argue the pullback was just sentiment, not a capex inflection.

Key Decisions for Investors

• Long RDDT into the Aug. 18 S&P 500 inclusion, but treat it as a 1-2 week flow trade: add on any pre-rebalance pullback, then trim into the event. Falsifier: if the stock stalls despite inclusion-driven buying, assume the passive flow is already embedded and fade the move.
• Short AMAT on strength over the next 1-3 weeks, or pair it against a broader semi basket like SMH to isolate company-specific de-rating risk. Risk/reward favors 1x downside to ~1.5x upside if semi capex commentary stays soft; cover if management raises forward orders or bookings inflect.
• Avoid chasing WDAY after the rumor-driven move unless there is a formal bid or process update. If shares retrace, a small call-spread structure is the only way I’d express M&A optionality; otherwise the expected value is poor because implied vol is likely overpaying for a low-conviction takeout path.
• Start building SNDK on pullbacks for a 3-6 month re-rating trade, using staged entries rather than momentum chasing. The thesis only works if long-term agreements hold margins above the old cycle pattern; exit if gross margin or pricing discipline rolls over.