Forty-seven of 55 top-200 alpha cohort holders in $AMGN are fresh initiations as of Q1 2026 — one added, zero trimmed, and seven held flat from the prior quarter. The structural fact here is the near-wholesale entry: this is not incremental rotation, it is a cohort arriving at a name it largely did not hold at end-2025.
The highest-conviction new entrant is Iat Reinsurance Co. Ltd., which opened at 16.02% of portfolio — an outlier by any measure in a cohort whose average weight sits at 0.68%. Sectoral Asset Management Inc. initiated at 3.01% and Hamel Associates, Inc. at 2.11%, both meaningful first positions. Bellevue Group AG, the sole adder in the cohort, moved from 0.12% to 2.55% (+2.43pp), the largest delta among continuing holders.
The aggregate picture is wide dispersion: weights range from effectively 0.00% (Corsicana & Co.) to 16.02%, with most initiations clustered well below 0.5%. The 0.68% cohort average is pulled upward by that single outsized Iat Reinsurance position; strip it out and the median new entrant is a sub-0.2% toe-hold. Seven holders — including Parvin Asset Management, LLC at 1.55% and Fiduciary Alliance LLC at 0.63% — carried positions flat from Q4 2025, providing the only continuity in an otherwise new-money quarter.
Forty-seven simultaneous initiations in one name across a single quarter is a structural curiosity. Whether that reflects index reconstitution mechanics, a common rebalancing template, or genuine independent conviction is not answerable from 13F data alone — but the uniformity of direction is worth noting.