Everything I read out of CIOE this week was a seller talking. $LITE on laser power tiers, $COHR on ultra-high-power ramps, $POET on 6.4T, Sivers on price rises. So I went looking for a buyer, and found one who had already answered the central question in public, in May, and answered it the other way. The sellers' position, from Lumentum management at a broker conference on 9 September: "There's a great concern what happens to the laser when it's so close to the heat source … there's a strong desire to move the laser outside." Two reasons for keeping the light source external. Reliability, and heat. Chen Qin, optical network architect at Alibaba Cloud, speaking at an xPO forum in Shanghai on 28 May, in remarks the CIOE organisers published themselves: deployment of 400G and 800G optical modules, now in the tens of millions, has thoroughly validated laser reliability. The spread of liquid cooling has effectively resolved the thermal bottleneck. NPO and CPO, in his words, now fully possess the objective conditions for putting the laser inside. He then called on the industry to push laser integration forward together. Translation mine. Both of the seller's reasons, marked settled by the customer, fifteen weeks earlier. That is the part worth sitting with, because the external light source story is load-bearing right now. It is the reason indium phosphide capacity is being prepaid years out, the reason a 70 mW part and a 400 mW part are suddenly different businesses, the reason anyone is modelling ELS modules as a separate line at all. His architecture choice is more specific than the headline. Scale-out keeps pluggables, with OSFP iterating. Scale-up moves to near-package or co-packaged, and at 224G per lane and below he says NPO has ample headroom and can fully reuse the existing supply chain. CPO he calls the long-term direction, with its current obstacles named as immaturity and single-vendor lock-in. That last phrase explains something I wrote about earlier this week. If the buyer's stated problem with co-packaged optics is being locked to one vendor, then a group of suppliers writing a common pluggable socket for optical engines is not a standards exercise. It is the answer to a customer objection. And the dates do not line up the way the market has them. Alibaba Cloud lit the first 3.2T NPO system to the OIF standard at the end of 2025, plans small-volume deployment at the end of this year and volume deployment next year. Its 6.4T UPO work expects system bring-up in the second half of this year and beta by year end. Against that, CPO was dated this month by three separate parties to the end of 2027 at the earliest. Near-package is roughly a year ahead, on the customer's own calendar. What I would not do is over-read one buyer. This is a single hyperscaler, in China, with its own silicon and its own supply constraints, and the US hyperscalers sit inside a different vendor ecosystem. It was also May, and plans stated in May are not deliveries. But nobody has publicly walked it back, and the supplier arguments this week were made as though the objection had never been raised. What would change my read: a Western hyperscaler putting a comparable schedule on record, either way. Also worth watching whether VCSEL-based designs gain ground, since he specifically noted they support an internal laser and need no polarisation-maintaining fibre, which removes two of the cost lines the external route carries. Friday's close: $LITE 931.68, $COHR 305.21, $POET 8.01, $AAOI 105.89, $AXTI 66.06.