If you’re wondering who owns the Boston tech scene, you might want to consider a couple of West Coast companies. A little over a year after buying Endeca for a billion dollars, database giant Oracle has acquired Bedford networking firm Acme Packet for $2 billion.

Meanwhile, social-media firm Twitter had no presence in Boston until the past week, when it acquired Crashlytics and Bluefin Labs, each startup for $100 million or more. It remains to be seen how big Twitter Boston will get, but already 2013 is looking like the year Boston tech sold out.

In other innovation news….

Biogen Idec is paying more than $3 billion to buy out its partner Elan Corporation’s interest in a drug for relapsing forms of MS. Biogen is the world’s biggest provider of MS drugs.

Our startup of the week is DataXu, a Boston company that has just raised $27 million, bringing its total haul to $65 million since 2007. The bigger trend is that advertisers are starting to pay for software, instead of just campaigns, to reach customers.

And lastly, MIT is trying to do more to encourage entrepreneurship. The school’s Computer Science and Artificial Intelligence Lab is starting a new class focused on building tech startups. The ultimate goal, which is shared with other institutions around town, is to help create one or two big companies — that won’t get acquired before their time.