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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 TechnologyUS1029.00-0.66%-4.27%+5.28%+9.82%+144.66%+423.99%USD
005930.KSSamsung ElectronicsKorea262000.00-2.42%-2.42%+2.54%-17.61%+46.86%+217.36%KRW
000660.KSSK hynixKorea1681000.00-2.44%-5.35%+2.06%-28.25%+102.53%+380.14%KRW
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FAQ · from the current data · as of 2026-10-09

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 2026-10-09: leading — Micron Technology (MU) +5.28%; Samsung Electronics (005930.KS) +2.54%; SK hynix (000660.KS) +2.06%. Lagging — SK hynix (000660.KS) +2.06%; Samsung Electronics (005930.KS) +2.54%; Micron Technology (MU) +5.28%. Returns are close-to-close in each name's trading currency.

Which HBM Memory names have done best over one year?

As of 2026-10-09: Micron Technology (MU) +423.99%; SK hynix (000660.KS) +380.14%; Samsung Electronics (005930.KS) +217.36%. Weakest: Samsung Electronics (005930.KS) +217.36%; SK hynix (000660.KS) +380.14%; Micron Technology (MU) +423.99%.

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.