OpenAI rival Anthropic has officially closed a deal to raise $3.5 billion at a valuation of $61.5 billion, the company told Bloomberg — cementing its place as one of the largest startups in the world.The higher valuation, which includes the new capital raised, comes as Anthropic’s business is growing quickly. Late last year, the company’s annual revenue run rate was about $1 billion, according to a person familiar with the matter. So far this year, that number has increased by 30%, said the pers...