13F Portfolios

RUSH ISLAND MANAGEMENT, LP 13F: Portfolio & Holdings

This page tracks the 13F filings for RUSH ISLAND MANAGEMENT, LP (SEC CIK 0001736465), a NEW YORK-based hedge fund managing $1.50 billion across 22 reported positions as of Q1 2026, per its quarterly SEC Form 13F-HR filing. The Q1 2026 13F filing shows 97.9% of Rush Island's reported portfolio concentrated in Real Estate.

By portfolio weight, the top holdings are ESSEX PPTY TR INC (ESS) at 13.12%, SBA COMMUNICATIONS CORP (SBAC) at 11.30%, and KILROY REALTY CORP (KRC) at 9.20%. Ranked by the share of each peer fund's 13F equity portfolio that overlaps with Rush Island's disclosed positions as of Q1 2026, the closest peers are Conversant Capital 13F (72.9%), Long Pond Capital 13F (26.3%), and AKRE 13F (6.8% overlap).

Most recently, the manager opened a new position in INVITATION HOMES INC (INVH) (7.06%), fully exited UDR INC (UDR) , added to KILROY REALTY CORP (KRC) (+84.54% shares), and trimmed FEDERAL RLTY INVT TR NEW (FRT) (-50.31% shares). View the full Q1 2026 allocation shift and trading report →

13F AUM
$1.5B
Equity Positions
22
Top-10 Concentration
80.2%
Largest Sector · 97.9%
Real Estate
Longest-Held Position · 19 qtrs
NNN
Median Holding Period
3 Qtrs

Top 10 Holdings — Rush Island — Q1 2026

Largest 13F positions disclosed by Rush Island, ranked by portfolio weight. Full multi-quarter history and the broader institutional holder base for each ticker linked per row.

Top 10 disclosed equity positions for Rush Island in Q1 2026 — ranked by portfolio weight; share count and market value sourced from SEC Form 13F-HR filings.
# Issuer Ticker Sector Weight Position Value Detail
1 ESSEX PPTY TR INC ESS Real Estate 13.12% $195.5M Position History All Holders
2 SBA COMMUNICATIONS CORP SBAC Real Estate 11.30% $168.4M Position History All Holders
3 KILROY REALTY CORP KRC Real Estate 9.20% $137.1M Position History All Holders
4 NNN REIT INC NNN Real Estate 8.74% $130.3M Position History All Holders
5 HEALTHCARE RLTY TR HR Real Estate 8.23% $122.8M Position History All Holders
6 VENTAS INC VTR Real Estate 7.70% $114.7M Position History All Holders
7 INVITATION HOMES INC NEW INVH Real Estate 7.06% $105.3M Position History All Holders
8 FIRST INDUSTRIAL REALTY TRUST, INC. FR Real Estate 6.81% $101.5M Position History All Holders
9 FEDERAL RLTY INVT TR NEW FRT Real Estate 4.55% $67.8M Position History All Holders
10 INDEPENDENCE RLTY TR INC NEW IRT Real Estate 3.45% $51.5M Position History All Holders

View Rush Island's Q1 2026 allocation shift and trading report →

Latest

Portfolio composition

Sectors, concentrations, and a tap-through treemap of every position in the fund's latest 13F.

Allocation by stock22 positions · click any tile for institutional holders
Allocation by sector4 sectors · same palette as the stock tiles

Quarterly shiftsQ1 2026 vs previous quarter

Top movers in Rush Island's Form 13F versus the prior reporting quarter. Δ Weight is the change in portfolio weight (percentage points); Δ Shares is the percent change in share count.

Top buys
CompanyTickerΔ WeightΔ Shares
KILROY REALTY CORPKRC+3.05%+84.54%
ESSEX PPTY TR INCESS+2.70%+26.79%
SITE CTRS CORPSITC+0.01%+11.43%
AMERICOLD REALTY TRUST INCCOLD+0.03%+5.76%
Top sells
CompanyTickerΔ WeightΔ Shares
FEDERAL RLTY INVT TR NEWFRT-3.54%-50.31%
SIX FLAGS ENTERTAINMENT CORPFUN-0.03%-21.45%
HEALTHCARE RLTY TRHR-1.31%-19.79%
NNN REIT INCNNN-0.75%-19.14%
SBA COMMUNICATIONS CORPSBAC-2.94%-16.92%
Top exited positions

Waterfall analysis

Top movers versus the prior reporting quarter. Left panel bridges market-value change in USD millions; right panel shows share-count change in %.

Δ Market value-$109.6M · -6.85% QoQ
Δ Shares heldNet +12.83% vs. prior quarter

Holding period analytics

Distribution of holding periods for all 108 stocks the fund has ever held (up to selected quarter):

Which Funds Hold a Similar Portfolio to Rush Island?

Ranked by percentage of the peer fund's 13F equity portfolio that overlaps with Rush Island's positions in Q1 2026.

Funds with the most portfolio overlap with Rush Island in Q1 2026 — Ranked by overlap percentage
# Fund Shared Positions Overlap %
1 Conversant Capital 13F 4 72.9%
2 Long Pond Capital 13F 5 26.3%
3 AKRE 13F 1 6.8%
4 Dendur Capital 13F 1 6.5%
5 ShawSpring Partners 13F 1 5.1%

How Has Rush Island's AUM Changed Over Time?

Quarterly 13F-reported AUM for Rush Island, derived from aggregate reported position market values disclosed to the U.S. SEC.

Methodology & FAQ

How We Track Rush Island Holdings

Our data is systematically aggregated directly from quarterly Form 13F-HR disclosures submitted to the U.S. Securities and Exchange Commission (SEC).

  • Who Must File (Reporting Threshold): This dataset includes filings from U.S. institutional investment managers, hedge funds, mutual funds, university endowments, and family offices managing at least $100 million in Section 13(f) securities (including equities, options, convertibles, ETFs, and warrants).
  • What is Included (Data Scope): By regulation, 13F filings include long positions in U.S. exchange-listed stocks, ETFs, shares of closed-end investment companies, and convertible debt, as defined in the SEC's official Section 13(f) securities list . For listed options (calls/puts) the reported value is based on the notional value.
  • Portfolio Weight Explained (Metric Definition): “Portfolio Weight” shows how much of a fund's total reported 13F portfolio value (excluding listed options) is allocated to a specific position on the reporting date.
  • How to Use This Data (Interpretation): Quarter-over-quarter changes in shares and portfolio weight reflect a combination of active trading and market price movements. These are descriptive metrics of fund allocation, not explicit buy or sell signals.
What does Rush Island's 13F filing disclose about their portfolio?

A Form 13F-HR filed by Rush Island with the U.S. SEC discloses all long positions in Section 13(f) securities — U.S.-listed equities, ETFs, closed-end funds, and listed put/call options — held at quarter-end with a market value of at least $200,000 or 10,000 or more shares. Pactolio aggregates these filings to surface Rush Island’s reported portfolio weights, share counts, and quarter-over-quarter allocation shifts in a structured format. The filing represents a point-in-time snapshot of disclosed long-side exposure, not a real-time or complete view of the fund’s total book.

How do you measure conviction in Rush Island's portfolio allocations?

Conviction is measured by portfolio weight — the percentage of Rush Island’s total reported 13F market value allocated to a given position — rather than by absolute share count or dollar value alone. A position representing a disproportionately large share of the fund’s disclosed book signals high-conviction allocation, regardless of whether it ranks among the fund’s largest absolute holdings. Tracking how that weight changes quarter-over-quarter separates active reallocation decisions from passive price appreciation drift.

What is excluded from Rush Island's 13F — short positions, swaps, and derivatives?

SEC Form 13F requires disclosure of long positions only. Specifically excluded are: short interest, total return swaps, credit default swaps, and all OTC derivatives — none of which appear in 13F filings regardless of position size. Listed put and call options must be disclosed but are excluded from portfolio weight calculations on this platform so that reported weights reflect direct equity exposure and remain comparable across filers. This means Rush Island’s 13F represents the reported long book, which may differ materially from its net economic exposure.

When is Rush Island's 13F data available, and how large is the reporting lag?

Investment managers must submit Form 13F within 45 calendar days of each quarter-end (the T+45 deadline). Pactolio ingests filings directly from SEC EDGAR as they are published — managers who file early appear in our system before the deadline, while late filers are captured on their actual filing date. The quarter label shown at the top of this page reflects the most recently processed 13F cycle for Rush Island. The inherent reporting lag means the data always reflects positions as of the prior quarter-end, not current holdings.

Who must file a Form 13F with the SEC, and does Rush Island qualify?

Under SEC Rule 13f-1, any investment manager — including hedge funds, family offices, registered investment advisers, pension funds, and university endowments — that exercises investment discretion over $100 million or more in Section 13(f) securities at any point during a calendar year must file Form 13F for that year. Rush Island meets this threshold, which is why its holdings are publicly disclosed and accessible on this platform. The $100 million threshold is evaluated on a rolling basis, meaning new filers can enter and existing filers can exit the disclosure regime as AUM crosses that boundary.