Loomis Sayles Q1 2026: A Concentrated Megacap-Growth Book

Loomis Sayles reported a $74.33B U.S. equity book for the quarter ended March 31, 2026 (Form 13F-HR, accession 0000312348-26-000026, filed 2026-05-14), and the portfolio is a study in growth conviction held through a drawdown. Its largest position, Nvidia (NVDA), is $7.15B — 9.62% of the entire book — and the rest of the top tier reads like a roster of megacap-growth leaders: Alphabet, Tesla, Meta, Amazon, and Netflix. Every one of the ten largest holdings was held roughly flat quarter over quarter, even as the reported value fell 9.9% from $82.47B.

What a casual 13F summary misses is how concentrated and how deliberately growth-tilted this book is. This is not an index sleeve that happens to own big tech; it is an active growth manager expressing high-conviction positions, with nearly 10% of assets in a single semiconductor name and a top six dominated by the market's fastest-growing franchises. The 9.9% decline in value, against flat positions, is the megacap-growth drawdown passing through a static book — not selling.

For readers, the signal is the conviction itself: Loomis Sayles did not flinch on its growth leaders during a down quarter.

Nvidia anchors a growth book

At 9.62% of assets, Nvidia is by far the largest position — an unusually large single-name weight for a $74B portfolio. Behind it sit Alphabet's GOOGL shares at 6.71%, Tesla (TSLA) at 6.33%, Meta (META) at 5.74%, Amazon (AMZN) at 5.14%, and Netflix (NFLX) at 4.91%.

The remainder of the top ten — aerospace name Boeing (BA), payments leader Visa (V), Oracle (ORCL), and Microsoft (MSFT) — reinforces the growth-and-quality character. The ten largest positions are a substantial share of the portfolio, with the long tail spread across more than a thousand reported names.

The growth cluster, quantified

The six megacap-growth leaders at the top — Nvidia, Alphabet, Tesla, Meta, Amazon, and Netflix — together account for roughly 38.5% of the entire book. That is an enormous concentration in a single style factor, and it defines the portfolio's risk and return profile: when high-multiple growth leads, this book wins; when it corrects, the book gives back, exactly as the 9.9% value decline this quarter shows.

Crucially, Loomis Sayles did not trim these names into the decline. Holding the growth cluster flat through a drawdown is itself an active decision — a statement that the manager's thesis on these businesses is intact regardless of quarterly price action.

What it means for 13F readers

Loomis Sayles offers a clean read on growth conviction. The portfolio's fortunes are tied to a concentrated set of megacap-growth leaders, held with conviction rather than traded around. The most informative thing to watch is not the headline value, which moves with the growth factor, but whether the manager ever changes the size of its Nvidia and Tesla weights — those would be the real signals. Track the firm's quarter-over-quarter holdings on the Loomis Sayles filer page.

FAQ

What is Loomis Sayles?

Loomis Sayles is an active asset manager known for its growth-equity and fixed-income strategies. It reported a $74.33B U.S. equity 13F book for the quarter ended March 31, 2026.

What is Loomis Sayles' largest holding in Q1 2026?

Nvidia (NVDA) is the largest position at $7.15B, or 9.62% of the book — an unusually large single-name weight that anchors a concentrated growth portfolio.

How concentrated is Loomis Sayles in megacap growth?

Its six largest growth names — Nvidia, Alphabet, Tesla, Meta, Amazon, and Netflix — together make up roughly 38.5% of the book, defining its style and risk profile.

Why did Loomis Sayles' 13F value fall in Q1 2026?

The reported value fell 9.9% to $74.33B, but the top holdings were held roughly flat. The decline reflects the megacap-growth drawdown passing through a static book, not selling.