—
C+
C+ The full Closelook — membership. Open the C+ overview
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
000660.KSSK hynixKorea1745000.00-0.80%-5.83%+16.33%-35.01%+79.90%+558.93%KRW
MUMicron TechnologyUS977.50+5.50%+0.01%+3.91%-6.30%+111.79%+516.37%USD
005930.KSSamsung ElectronicsKorea252500.00-0.39%-6.13%+2.02%-30.34%+30.49%+264.32%KRW
← Back to Rubin Build-Out 100 Read the AI Chip Build-Out dossier →

FAQ · from the current data · as of 2026-09-17

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 2026-09-17: leading — SK hynix (000660.KS) +16.33%; Micron Technology (MU) +3.91%; Samsung Electronics (005930.KS) +2.02%. Lagging — Samsung Electronics (005930.KS) +2.02%; Micron Technology (MU) +3.91%; SK hynix (000660.KS) +16.33%. Returns are close-to-close in each name's trading currency.

Which HBM Memory names have done best over one year?

As of 2026-09-17: SK hynix (000660.KS) +558.93%; Micron Technology (MU) +516.37%; Samsung Electronics (005930.KS) +264.32%. Weakest: Samsung Electronics (005930.KS) +264.32%; Micron Technology (MU) +516.37%; SK hynix (000660.KS) +558.93%.

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.