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Ticker · held by 3 filers

MTRX

MATRIX SVC CO

All tracked filers currently holding MTRX, ranked by position size. Each row links through to the filer's full portfolio.

Total value held
$39.1M
Total shares
3,851,958
Filers holding
3 · 4 positions
Caveat
long only · 13F-eligible managers only
Filers holding MTRX
# Filer Class Shares Value (USD) % of port
1 BlackRock · Larry Fink COM 3,351,349 $33.3M 0.00%
2 Renaissance Technologies · Jim Simons (founder) COM 250,600 $2.9M 0.00%
3 Citadel Advisors · Ken Griffin COM 228,409 $2.7M 0.00%
4 Citadel Advisors · Ken Griffin CALLCOM 21,600 $252.7K 0.00%

What this is

This page reverses the usual 13F view: instead of "what does Buffett hold," it answers "who holds NVDA?" Across the dozen tracked filers, all current 13F-disclosed holders of MTRX are listed, with the position size and what fraction of each filer's overall portfolio it represents.

Caveats: only the filers tracked here are included (~12 names) — not the whole 13F universe (~6,000 filers). Position values are at the most recent quarter-end, not current market price. Only long positions are visible; shorts and synthetics aren't.

v0.2 · 2026 · data via SEC EDGAR · CUSIP→ticker via OpenFIGI