Historical position

George Soros’s Mercury Sys Inc (MRCY) position

Reported position history, portfolio importance and verified filing changes from public SEC disclosures.

Soros Fund ManagementVerified through Q2 2026
Relationship snapshot

At a glance

The full verified relationship, including prior ownership episodes and exits where supported.

First reportedQ2 2007Earliest verified positive filing snapshot
Latest statusHistorical positionBased on the latest supported relationship state
Peak shares2.29MHighest verified quarter-end share count
Quarters reported28Verified quarters with shares above zero
What happened?

Soros Fund Management first reported Mercury Sys Inc in Q2 2007. The reported position was increased and reduced across later filings. Verified positive position history runs through Q3 2014. The current relationship status cannot be determined reliably from supported data.

Verified SEC history

Position over time

See the same verified relationship through reported shares, portfolio weight or reported value.

Metric

Gaps indicate periods that cannot be safely connected or where a verified corporate action changes the raw share scale. Stock price, when available, is market context and not a transaction price.

Key filing events

What changed

Latest filing plus the most meaningful reported changes. Unchanged quarters are collapsed by default.

Q3 2014
Bought 384.0% more+640.00K shares · 806.67K shares reported after the change
Filing context

Quarter-end price $11.01 · Estimated holding basis $11.55

Q2 2014
Sold 80.1% of the position−670.00K shares · 166.67K shares remained
Filing context

Quarter-end price $11.34 · Estimated holding basis $13.63

Q1 2014
Sold 22.3% of the position−240.72K shares · 836.67K shares remained
Filing context

Quarter-end price $13.21 · Estimated holding basis $13.63

Q4 2013
Sold 29.5% of the position−450.38K shares · 1.08M shares remained
Filing context

Quarter-end price $10.95 · Estimated holding basis $13.63

Q3 2013
Bought 20.6% more+261.10K shares · 1.53M shares reported after the change
Filing context

Quarter-end price $9.99 · Estimated holding basis $13.63

Q2 2013
Bought 0.2% more+2.87K shares · 1.27M shares reported after the change
Filing context

Quarter-end price $9.22 · Estimated holding basis $14.38

3 unchanged quarters are collapsed by default.

Portfolio importance

How important was Mercury Sys Inc in Soros Fund Management’s reported portfolio?

Relative importance is measured only within the verified primary non-option reported portfolio for each quarter.

Last reported portfolio weight0.1%Q3 2014
Last reported rank#151of 245 reported positions
Peak portfolio weight0.7%Q4 2011
Best historical rank#25Q4 2011
At peak importanceQ4 2011
MRCY
0.7%
Largest holding
18.2%
Cross-investor discovery

Who else owns Mercury Sys Inc?

Also reported by 1 other tracked investor in their latest verified filings.

Joel GreenblattGotham Asset Management
MRCY0.0% of reported portfolio
Explore Mercury Sys Inc across all tracked investors →
SEC evidence & methodology

SEC filing evidence

Market context and filing-derived values are kept separate from actual transaction prices, which 13F filings do not disclose.

Latest verified stock price$85.282026-09-18

Market context only; not an investor transaction price.

Latest filing quarter-end price$11.01Q3 2014

Derived from validated reported value and shares where supported.

Estimated holding basis$11.55Historical reference — not actual purchase price

Calculated from supported filing history.

Latest verified investor filingQ2 2026 · filed 2026-08-14
Open SEC filing ↗

This tracker follows Soros Fund Management LLC’s Form 13F disclosures—not George Soros’s personal brokerage account. George Soros founded the firm; its current CEO and chief investment officer is Dawn Fitzpatrick. Form 13F does not reveal exact trade dates, execution prices or the purpose of an option position.