Open API card issuing and processing platform Marqeta is closing in on a $250 million Series E round...: Open API card issuing and processing platform Marqeta is closing in on a $250 million Series E round at a $1.875 billion valuation, according to TechCrunch. The figures come from a filing provided to TechCrunch and are currently provisional, but the round could close within weeks, the blog claims the blog.