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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) 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 TechnologyUS1016.59+6.10%+8.98%+15.33%+17.66%+174.65%+719.63%USD
005930.KSSamsung ElectronicsKorea255500.00+2.20%-0.58%+3.86%-22.34%+48.68%+261.93%KRW
000660.KSSK hynixKorea1647000.00+3.20%-3.91%-1.26%-20.43%+93.99%+558.81%KRW
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FAQ · from the current data · as of 2026-09-04

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 2026-09-04: leading — Micron Technology (MU) +15.33%; Samsung Electronics (005930.KS) +3.86%; SK hynix (000660.KS) -1.26%. Lagging — SK hynix (000660.KS) -1.26%; Samsung Electronics (005930.KS) +3.86%; Micron Technology (MU) +15.33%. Returns are close-to-close in each name's trading currency.

Which HBM Memory names have done best over one year?

As of 2026-09-04: Micron Technology (MU) +719.63%; SK hynix (000660.KS) +558.81%; Samsung Electronics (005930.KS) +261.93%. Weakest: Samsung Electronics (005930.KS) +261.93%; SK hynix (000660.KS) +558.81%; Micron Technology (MU) +719.63%.

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.