Keystone Acquisition Corp.

KEYYU

Exchange: Nasdaq
Industry: Blank Checks
SEC CIK: 0002102771

SEC filings (opens in a new tab)

No open-market purchases or sales by Keystone Acquisition Corp. insiders were filed in the last 90 days; 29 institutions reported holding it in 13F filings for Q2 2026, worth $135.2M in total; no superinvestor holds it.

Other share classesKEYY KEYYW

Q2 2026 vs. Q1 2026

How the institutions holding Keystone Acquisition Corp. changed between Q1 2026 and Q2 2026.

All holders in Q2 2026 All holders in Q1 2026

13F holders of KEYYU: Q1 2026 compared with Q2 2026
Measure	Q1 2026	Q2 2026	Change
Holders	0	29	+29
Shares	0	13.5M	+13.5M
Value	$0	$135.2M	+$135.2M

New holders (29)

Institutions that held Keystone Acquisition Corp. at the end of Q2 2026 but not at the end of Q1 2026.

Institutions new to KEYYU in Q2 2026
Institution	Shares	Value	% of portfolio
Magnetar Financial LLC	2,000,000	$20.1M	0.18%
CNH Partners LLC	1,723,275	$17.3M	0.25%
LMR Partners LLP	1,300,000	$13.1M	0.10%
Healthcare of Ontario Pension Plan Trust Fund	1,250,000	$12.6M	0.02%
Alberta Investment Management Corp	800,000	$8.05M	0.05%
HGC Investment Management Inc.	800,000	$8.03M	1.59%
Fort Baker Capital Management LP	600,000	$6.02M	0.48%
BNP Paribas Arbitrage, SA	526,725	$5.29M	0.00%
Millennium Management LLC	500,000	$5.02M	0.00%
Radcliffe Capital Management, L.P.	499,900	$5.02M	0.38%
Centiva Capital, LP	425,000	$4.27M	0.14%
Picton Mahoney Asset Management	400,000	$4.02M	0.04%
Decagon Asset Management LLP	375,000	$3.77M	0.75%
Whitebox Advisors LLC	350,000	$3.51M	0.06%
Moore Capital Management, LP	300,000	$3.01M	0.07%
Lineage Point Capital LP	295,719	$2.97M	0.61%
Rivernorth Capital Management, LLC	200,000	$2.03M	0.10%
Calamos Advisors LLC	200,000	$2.02M	0.01%
Schonfeld Strategic Advisors LLC	200,000	$2.01M	0.01%
Toronto Dominion Bank	199,900	$2.01M	0.00%
Ghisallo Capital Management LLC	150,000	$1.51M	0.03%
Aristeia Capital LLC	144,062	$1.45M	0.02%
DLD Asset Management, LP	100,000	$1.00M	0.08%
Susquehanna International Group, LLP	40,000	$401.6K	0.00%
Abc Arbitrage SA	30,000	$301.2K	0.03%
HRT Financial LP	22,330	$224.0K	0.00%
Clear Street Group Inc.	20,553	$206.4K	0.00%
Longfellow Investment Management Co LLC	8,642	$86.8K	0.02%
UBS Group AG	1,040	$10.4K	0.00%

Sold out (0)

Institutions that held Keystone Acquisition Corp. at the end of Q1 2026 and filed for Q2 2026 without it.

None.