Nextdoor, a San Francisco-based platform for creating neighborhood-based private social networks, has raised $21.6 million in new VC funding. Greylock Partners led the round, and was joined by Bezos Expeditions, Google Ventures and return backers Allen & Co., Benchmark, DAG Ventures, Pinnacle Ventures and Shasta Ventures. www.nextdoor.com
RightScale Inc., a Santa Barbara, Calif.-based provider of enterprise cloud management solutions, has raised $15 million in fourth-round funding, according to a regulatory filing. The company previously raised more than $42 million, from Tenaya Capital, DAG Ventures, Benchmark, Index Ventures and Presidio Ventures. www.rightscale.com
Nok Nok Labs, a Palo Alto, Calif.-based online authentication startup, today came out of stealth mode and announced a previously-undisclosed $15 million Series A round from DCM and Onset Ventures. www.noknok.com
Holaira Inc. (f.k.a. Innovative Pulmonary Solutions), a Bellevue, Wash.-based developer of minimally-invasive products to make breathing easier for patients suffering from obstructive lung diseases, has raised $10 million in Series C funding. Return backers included Advanced Technology Ventures, Morgenthaler Ventures, Split Rock Partners and Versant Ventures.www.innovativepulmonary.com
Simulmedia, a New York-based digital advertisement targeting platform for television, has raised $5 million in new VC funding, according to an SEC filing. TechCrunch reports that the round came from return backers Avalon Ventures, Time Warner Investments and Union Square Ventures. www.simulmedia.com
Oxford Photovoltaics Ltd., a UK-based developer of solid-state dye sensitized solar cells for the building integrated photovoltaic sector, has raised £2 million in VC funding. MTI Partners led the round, and was joined by the University of Oxford and individual angels. www.oxfordpv.com
