Three companies published the same cost target. NVIDIA ($NVDA) wants co-packaged optics under 1.5 picojoules per bit. IBM ($IBM) is going for under 1. Intel ($INTC) is targeting under 5 across the package, end to end. Different numbers, because the engineering is different. Then all three name the same cost. 0.1 dollars per gigabit per second. Power targets diverge because the physics diverges. A cost target that lands on the same figure three times did not come up from the engineering. It came down from the customer. Which would be fine, except for what the customer cannot do. The director who set up Resonac's (TSE: 4004) US-JOINT consortium in Silicon Valley told Nikkei that hyperscalers and fabless companies are strong at simulation, but there are few environments where you can verify an actual semiconductor package. So the people setting the number cannot test against it. On the manufacturing side, the same week's coverage says who bears final responsibility for quality assurance is still an open question. Foundries and OSATs are not used to volume optical production, and the division of labour has not been agreed. The instruments exist. Keysight ($KEYS) announced a 220 GHz lightwave component analyzer on 12 March and showed it at OFC. The measurement is possible. The signature is not assigned. Here is why that matters more than it sounds. Both failure modes in this stack are local, not average. A fiber core and a waveguide differ in cross section by roughly 800 times, so a misalignment at nanometre scale becomes a coupling loss you cannot average away. On the thermal side a chip can run cool on average and still fail from one hot spot. Resonac buys test chips from imec that reproduce over 1000 watts and can heat a single region of the die. Testing that used to pass on averages now has to catch the local case. That means more test time per part, on parts that are already singulated. The back end already had the thinnest margins in the industry. So the layer that gets paid here is not the one making the optics. It is the one deciding whether they passed. Advantest (TSE: 6857) and Teradyne ($TER) are the duopoly in that seat. Keysight sits beside it. One more line, because the geography is odd. Resonac partnered with Purdue in May for thermal analysis. SK hynix (KRX: 000660) is putting 3.87 billion dollars into an advanced packaging site on land held by a Purdue-affiliated foundation in Indiana. A Japanese materials company and a Korean memory maker are working at the same university. Where a responsibility gap sits open, someone eventually charges a toll to close it. What would change my read: if a foundry or an OSAT publicly takes final sign-off on CPO. Then this stops being an open seat. Sources, in order: Nikkei xTECH, 17 August 2026, two articles. Keysight press release, 12 March 2026. Nikkei BP, book on optoelectronic fusion, industry map section. My read, not advice.