ROCKET LAB CORP

Rocket Lab USA Inc (RKLB), the Long Beach-based small-launch and space-systems company whose Electron rocket and Photon satellite bus compete in the dedicated small-launch and cislunar-application markets, now anchors a $21.1 billion institutional register across 845 filers — a population that has jumped meaningfully in Q1 2026 on the back of multiple new passive entries that signal the name has crossed the liquidity and float thresholds triggering index inclusion. The most consequential move was Vanguard Portfolio Management opening a new $1.65 billion position and Vanguard Capital Management following with $1.56 billion simultaneously, a dual-entry pattern that is the fingerprint of multiple index products (S&P mid-cap, S&P small-cap, a broader total-market sleeve) cross-rebalancing into the name at the same review cycle; the companion new positions from Capital International Investors ($430M) and Vanguard Fiduciary Trust ($197M) reinforce that the passive layer of RKLB's register grew by several billion dollars this quarter. On the active side, BlackRock added $132 million to build a $2.4 billion position (now the single largest active holder), Jane Street's market-maker inventory grew by $368 million, Goldman Sachs initiated a new $300 million position, and Morgan Stanley and Westfield Capital added meaningfully. The only real headwind in the file was Capital World Investors — a Capital Group subsidiary — which reduced by $665 million, trimming its position roughly in half; UBS also cut by $169 million, and Ameriprise, Invesco, Bank of America, FMR, and Susquehanna were all lighter. The net read on RKLB's register: the denomination of the ownership structure has shifted materially in one quarter, driven by passive-mechanical flows rather than discretionary conviction, which is what you'd expect exactly at the moment a name crosses into index-eligible territory. The stock has not yet been added to the S&P 500 or a comparable broad-cap index based on public announcements, but the Vanguard dual-entry alone makes a strong circumstantial case that at least one index review during Q1 determined RKLB's float and liquidity satisfied inclusion criteria.