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Rubin Build-Out 100 · Sector S8 · Layer 3 · Assembly & Test

HBM Memory

High-bandwidth memory — the part of the AI compute stack that has actually run out of supply. Storage split out to its own sub-index in the 2026-06-30 reconstitution.

Equal-weight — 1d —
Cap-weighted — 1d —
Momentum (drift) — 1d —
Constituents — in this sector

Composite Index — since inception (Dec 30, 2025)

Three weighting variants of the same constituent basket, rebased to 1,000 at inception. EW = ticker-equal-weight with quarterly drift. CW = cap-weighted (10% cap; below ten names the cap is infeasible, so the sub-index is equal weight by construction) with semi-annual rebalance. MW = drift-only (1/N at inception, market does the tilting between rebalances). Click a legend entry to toggle its line.

Constituents

Every Rubin constituent tagged into this sector. Click a row to open the stock detail page with full chart + Money-Temperature scoring.

Ticker Company Region Last 1d 1w 1m 3m 6m 1y CCY
MUMicron TechnologyUS1080.53+0.81%+10.54%+15.82%-10.96%+182.91%+550.26%USD
005930.KSSamsung ElectronicsKorea285500.00+3.25%+12.62%+11.09%-16.15%+53.56%+297.75%KRW
000660.KSSK hynixKorea1862000.00+1.20%+5.86%+10.97%-28.96%+99.57%+514.07%KRW
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FAQ · from the current data · as of 2026-09-24

HBM Memory — data Q&A

What is the HBM Memory sub-index of the Rubin Build-Out 100?

3 constituents, listed across Korea, US, computed equal-weight, cap-weight and momentum-weight from the same basket and rebased to 1,000 at the index base date. Part of the Rubin Build-Out 100 — /indices/rubin/.

Which HBM Memory constituents lead and lag over one month?

As of 2026-09-24: leading — Micron Technology (MU) +15.82%; Samsung Electronics (005930.KS) +11.09%; SK hynix (000660.KS) +10.97%. Lagging — SK hynix (000660.KS) +10.97%; Samsung Electronics (005930.KS) +11.09%; Micron Technology (MU) +15.82%. Returns are close-to-close in each name's trading currency.

Which HBM Memory names have done best over one year?

As of 2026-09-24: Micron Technology (MU) +550.26%; SK hynix (000660.KS) +514.07%; Samsung Electronics (005930.KS) +297.75%. Weakest: Samsung Electronics (005930.KS) +297.75%; SK hynix (000660.KS) +514.07%; Micron Technology (MU) +550.26%.

How often does this sub-index update, and is it advice?

The worker recomputes the sub-index and every constituent's returns after each US close (prices converted to USD for the index level; per-name returns stay in local currency). This page is a data surface in an investment research diary — it describes constituents and returns, it recommends nothing.