"Domestic": the suspect(s) are US resident(s) or citizen(s) (majority, if multiple perpetrators).
"Terrorism": violence with intent to instill fear in a population (a.k.a. the shitty, imprecise definition commonly used in the media). Valid examples: bombing, mass shooting, widespread poisoning.
"Silicon Valley": any tech firm with an SF-area HQ or major office.
"Company": the target is any company-owned building and/or its employees as a group. Can happen outside SV, but the company must still be the primary target. If only a single individual is targeted, e.g. the CEO, it doesn't count under this nor under terrorism.
For the purposes of this question, the attack must occur with damage to persons or property, not only be threatened or thwarted.
1,000@JonathanRay Saw this now that I'm back. I'd say no, it's a gray area and I might have said yes, but if we're talking about the 2018 shooting then it's disqualified on those grounds. It was a vendetta, potentially a "mass shooting" but it's not clear to me that the purpose was to instill terror instead of just rage