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CPRXBearishCorporate Developmentsnews

High materiality7/10

Catalyst Pharmaceuticals Dropped from S&P SmallCap 600; SEI Replaces CPRX

Jul 9, 2026, 5:51 PM EDT1 sourcesAI-analyzed

Why it may matterVerify against the original reporting

Removal from a benchmark index often prompts selling by index funds or ETFs, creating near-term downside pressure. The CPRX move is tied to an acquisition, but until closing, the stock may face volatility and reduced float as funds adjust to the new composition.

AI summary

What happened, with direct paths to the underlying reporting

Solaris Energy Infrastructure will replace Catalyst Pharmaceuticals in the S&P SmallCap 600 ahead of July 15, 2026, per S&P Dow Jones Indices. CPRX is being removed as Angelini Pharma's acquisition of Catalyst closes, a development that could weigh on CPRX near term while SEI may see improved liquidity from index inclusion.

CPRX to leave S&P SmallCap 600 on July 15; SEI added.
Solaris Energy Infrastructure (SEI) will replace Catalyst in the index.
Angelini Pharma's Catalyst acquisition to close soon; CPRX impact tied to deal.
Index rebalancing may trigger passive selling of CPRX and liquidity shift.

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StockNews.AI groups source reporting, classifies the event, and measures subsequent price movement. This is informational research, not investment advice. Prices may be delayed or unavailable.

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