Luminus Devices, a VC-funded firm developing and selling solid-state lighting products, was sold to Chinese LED maker San'an for $22 million, according to LED news. Luminus' customers include LG, Acer, Zumtobel, U.S.-based EYE Lighting, Philips, Denmark's Martin, and Germany's Vialux. The firm's annual revenue in 2012 was $17 million, according to reports.

The lighting industry is going through a drawn-out transition to fluorescents and light-emitting diodes (LEDs), and 2013 has seen strong progress in the commercialization of LED lighting. There will be winners and losers along the way -- and in the case of Luminus Devices, it's safe to say the firm's VC investors were not winners this time. 

Luminus had collected more than $150 million in venture capital from Argonaut Private Equity, Braemar Energy Ventures, Paladin Capital Group, Stata Venture Partners, CMEA Ventures, Battery Ventures, DFJ, DFJNE, and Eastward Capital. The firm sold for $22 million to San’an Optoelectronics subsidiary Lightera.

Luminus is a relatively older startup, founded in 2002 with a “photonic lattice” LED technology and a focus on projection display that shifted toward general illumination and high-brightness applications such as street lighting. A twelve-year-old startup, even one with revenue and profit, is a challenge for many venture funds, which model faster returns and have ten-year partnerships.

Breaking into the lighting business is difficult. Consumers expect cheap products. Facilities managers and COOs expect rapid payback. And startups have to compete against 100-year-old incumbents in fragmented and inefficient supply chains. LEDs will eventually win in many applications -- but it's taking a long time.

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