Here is the structural fact, then the document. Once you have wrapped the gate all the way around the channel, the next way to gain density is to stop placing transistors side by side and start stacking them on top of one another. IBM was granted US12652849B2, "Backside contacts for stacked transistor structures with shifted channels," on June 9, 2026 (CPC H10D 64/254).
Stacked transistors — the complementary FET, or CFET, idea — put an n-type and a p-type device in a vertical stack instead of a horizontal pair, roughly doubling logic density in the same footprint. The unglamorous problem is contacts: how do you wire power and signal to a transistor buried under another one? This patent is about exactly that, combining stacking with the backside-contact approach so the buried device can still be reached.
The business read is about who stays relevant. IBM is not a volume foundry, but it runs a research operation whose IP feeds the whole leading edge through partnerships and licensing. A grant on the contact scheme for the post-GAA architecture is how IBM keeps a seat at the table where the next node is defined — and a potential licensing asset if stacking goes mainstream.
Be precise about what is and isn't claimed. The grant covers a specific contact structure for shifted-channel stacked devices; it is not a claim on CFET in general, and it is research-stage IP, not a manufacturing commitment from any fab. The honest framing is directional: the industry's most forward-looking players are already patenting the wiring for transistors that are stacked, not spread.
For anyone modeling the sector, the signal is timing. Backside power is shipping or near-shipping; stacked transistors are the lever after that. Patents like this one are the early footprints of a transition that will eventually show up as new tooling demand and new capex — years before it shows up in revenue. Read the IP to see where the money will have to go.
Trace it to the filing and the throughline holds: the density story did not end with gate-all-around, and the contact patent for stacked devices is the record of the industry already reaching for the next rung.