Latent Equity$AAPL's December margin guide and memory-chip margins past their 2018 peaks
Memory chip makers are earning record margins. $AAPL just showed who pays for it.
Apple guided December-quarter gross margin to 45–46%, down from 47.9% in the September quarter (about 1 point of that 47.9% came from tariff refunds).
On the call, Apple's CFO said the guide "includes primarily the impact of higher memory costs," plus some costs from ramping Siri AI. CEO John Ternus called memory pricing "unprecedented" and said he sees memory pricing continuing to increase beyond the December quarter.
The other side of that bill: SK hynix ($SKHY) posted a 79.7% operating margin in the September quarter, vs 56.7% at its 2018 peak. Samsung's chip unit (KRX: 005930) hit 72.4%, vs 55.6% at its 2018 peak, when the unit also included Display (our calc).
Why now: TrendForce says suppliers keep shifting capacity toward server memory, which leaves phone memory tight and could cut PC memory supply in 2027. It sees regular DRAM contract prices up 10–15% this quarter.
Our read: the AI buildout's cost is showing up first at buyers of everyday memory, not at the AI chip names. Apple is offsetting part of it with price increases and cheaper non-memory parts.
What would change our read: Apple's actual December margin at or above 47.9%, TrendForce's Q1 outlook showing DRAM prices flat or down, or SK hynix's margin falling back toward 56.7% in January.
Next check: $AAPL December-quarter print (late January 2027, est.) and $SKHY Q4 margin (late January 2027, est.)
Method and sources
Figures marked "our calc" are our own arithmetic on the cited primary sources (company filings, earnings releases, public datasets). Every figure was checked against its source before publication.
General research, the same for every reader. Not investment advice.