O'Shaughnessy Q1 2026: Quant Model Adds Across Megacaps

O'Shaughnessy Asset Management is a quant shop — its portfolios are built by factor models, not by analysts arguing over individual names — and its first-quarter 2026 filing reads exactly like one. Across its largest holdings, the pattern is strikingly uniform: the model raised Apple by 46%, Alphabet by 28%, Nvidia by 26%, Broadcom by 19%, Amazon by 17%, and Microsoft by 11%. When nearly every megacap moves up by a similar order of magnitude in the same quarter, you are not looking at stock-picking — you are looking at a systematic tilt.

That uniformity is the signature of rules-based investing. A discretionary manager picks winners and losers; a quant model ranks the whole universe on factors like value, momentum, and quality and rebalances toward whatever scores best. In Q1 2026, large-cap technology scored well, and O'Shaughnessy's model leaned in across the board. The reported 13F value rose 11.8% quarter over quarter to $18.04 billion, part of a book that has more than doubled over two years.

An across-the-board megacap tilt

Apple became the largest holding at $924.3 million (5.12%) after a 46% increase in shares, with Nvidia close behind at $826.0 million (4.58%), up 26%. The rest of the megacap complex followed the same direction: Microsoft up 11%, Alphabet up 22% (with its second share class up 28%), Amazon up 17%, and Broadcom up 19%.

The consistency is the tell. A model that increases exposure to seven different megacaps by double digits in one quarter is responding to factor scores, not forming a view on each company. For investors reading the filing, the takeaway is not "O'Shaughnessy loves Apple" — it is "the firm's factors currently favor large-cap quality and momentum," and the megacaps are simply where those factors point.

A broad, model-driven book

Beneath the megacaps, the portfolio is wide and systematic. O'Shaughnessy reports 500 positions — the platform's maximum — with the top ten accounting for under a quarter of the book and the remaining 76% spread across a long tail of factor-selected names.

The top holdings also include broad-market and bond ETFs, which a quant manager often uses for exposure or cash management rather than as conviction bets. That breadth is the point: where a concentrated manager expresses a few high-conviction ideas, a quant book expresses a process across hundreds of names. The individual position sizes are modest precisely because the edge is meant to come from the systematic tilt, not from any single stock.

A book that has doubled

O'Shaughnessy's reported value has grown almost without interruption.

From about $9.68 billion in mid-2024, the reported 13F value has climbed steadily to $20.12 billion by the first quarter of 2026 — more than doubling, with the position count pinned at 500 throughout. For a systematic manager, that kind of steady growth typically reflects asset inflows and market appreciation compounding together rather than episodic bets paying off. The smoothness of the climb is itself consistent with a rules-based process running at scale.

What it signals

For investors who track institutional positioning, O'Shaughnessy's first-quarter filing is a reminder to read the manager's method before reading its trades. The across-the-board megacap adds are not seven separate convictions; they are one factor signal expressed seven times. The actionable read is what the model is favoring — large-cap quality and momentum — and the recognition that a quant book's individual position changes are outputs of a process, not bespoke calls. That makes the direction of the tilt informative even when no single name is.

FAQ

What did O'Shaughnessy change in Q1 2026?
Its quant model raised exposure across the megacaps — Apple by 46%, Alphabet by 28%, Nvidia by 26%, Broadcom by 19%, Amazon by 17%, and Microsoft by 11% — a systematic tilt toward large-cap quality and momentum. Reported 13F value rose 11.8% to $18.04 billion.

Why did O'Shaughnessy increase so many megacaps at once?
It is a quant manager whose portfolio is built by factor models. When large-cap quality and momentum factors score well, the model rebalances toward the names that fit — producing uniform, across-the-board adds rather than individual stock-picking.

What is O'Shaughnessy's largest holding?
Apple, at $924.3 million or 5.12% of the portfolio after a 46% share increase, followed by Nvidia at $826.0 million (4.58%). The top ten account for under a quarter of the book.

How concentrated is O'Shaughnessy's portfolio?
Not very. It holds 500 positions with roughly 76% of the book outside the top ten — a broad, model-driven structure where the edge comes from a systematic tilt rather than a few large bets.