Seattle startup Flexe raised an additional $10 million as part of its Series C funding round announced in December. Flexe CEO Karl Siebrecht said there was more investor interest than anticipated. “That combined with our evolving assessment of how many growth opportunities there are in front of us to further invest in is what drove the expansion of the round,” Siebrecht said. Flexe initially raised $70 million in December as part of the round. Flexe operates a marketplace that gives retailers such as Walmart and Staples a way to purchase warehousing space on an on-demand basis.