Google’s TPU v9 could use fewer PCB layers than Amazon’s Trainium 4 while requiring more HDI build-up steps. We think total layer count alone would understate the manufacturing work involved. Taiwan sell-side research points to a 3-28-3 HDI design for Trainium 4 in Q3 2027 and a 6-12-6 design for TPU v9 in Q4 2027. That works out to 34 total layers for Trainium 4 and 24 for TPU v9. But TPU v9 would have six HDI build-up layers on each side of its inner stack, versus three for Trainium 4. Those outer layers are added through sequential lamination, with laser-drilled microvias connecting them. More build-up layers add processing steps and place greater demands on alignment and interconnect reliability. For AI PCB suppliers, the two designs would create different production requirements. High-layer-count capability and the ability to reliably manufacture deeper HDI structures both matter as cloud providers develop their next custom chips. $GOOG $AMZN

Google DeepMind has used AI agents to verify the actual compiled code behind Signal's encryption, down to the machine-code level. This is a huge step for software security: vulnerabilities can hide in the gap between a protocol's design and the code that implements it. The system, called AlphaProof Code, generated around 6.5 million lines of machine-checked Lean proofs covering key security properties of Signal's handshake and message ratchet. Google says the work took four weeks, a task that could previously have taken expert teams years. The researchers also reintroduced two previously fixed Signal bugs, and the system proved that both broke the specified security guarantees. The proofs cover specific properties under defined assumptions, but this is a remarkable demonstration of how AI could make formal verification practical for real-world software.

Google's $10M bid for Spirit Airlines' data to train AI would cover: - 1.9B emails across 91K accounts - 664M Teams items - 91M SharePoint/OneDrive files - 30M lines of code - Booking and airfare data Unions dropped objections after privacy safeguards. Court approval pending.

Google's $10M bid for Spirit Airlines' data to train AI has advanced after unions withdrew privacy objections. The data includes 500M Microsoft Teams chats and 100M emails. Personal data on 97M customers & sensitive employee records will be excluded, with stricter protections.

Google's new TPU 8i Max uses $ARM based Axion CPUs to prepare data and manage AI workloads, joining TPU 8t and 8i. That means 3 of Google's 4 next-gen TPU systems now use Arm host CPUs, versus x86 hosts previously. The fourth, TPU 8tx, uses $AMD EPYC CPUs.