Acacia Communications said it raised $20 million in a round led by Summit Partners and joined by existing investors Matrix Partners , Commonwealth Capital Ventures and Egan Managed Capital. Summit Partners Managing Director Peter Chung will join the company’s board.

Matrix Partners said its raised a $450 million 10th fund with a focus on early stage technology investing. The Boston-based firm with offices in Silicon Valley, China and India said the fund is its third consecutive $450 million fund.

Fastback Networks, a San Jose-based mobile infrastructure company, has closed a $15 million round led by the venture firm Matrix Partners. Existing investors, including Foundation Capital; Granite Capital; and Juniper Networks, through its Junos Innovation Fund, also participated in the Series B financing. Fastback Networks raised $11 million in Series A funding in 2011.

Matrix Partners, the Palo Alto, Calif.-based venture firm, has brought aboard a new general partner. Jared Fliesler joins the firm from the privately held payments company Square, where he served as VP of user acquisition and business operations. Prior to Square, Fliesler was an executive with Slide and is credited with helping to negotiate the company’s $200 million sale to Google in 2010.

Mobile advertising startup Adelphic Mobile has raised $10 million in a funding round led by Google Ventures and including previous investor Matrix Partners. Adelphic Mobile earlier this year raised $2 million in seed funding from Matrix Partners.

Conductor, a search engine optimization technology business, has secured $20 million in Series C financing led by Investor Growth Capital. Existing investors FirstMark Capital and Matrix Partners also participated in the round.

textPlus, a provider of free mobile communications worldwide, has raised $18 million in capital led by The Raine Group. Previous textPlus investors Kleiner Perkins Caufield Byers, Matrix Partners and GRP Partners have also joined in this fourth round of funding for the company. Proceeds will be used towards international expansion, product development and strategic acquisitions.

Work4 Labs has received $11 million in Series A funding from Matrix Partners and a group of select industry experts. Work4 Labs uses Facebook and other social networks to help businesses hire for positions at every level, from hourly workers to mid-level executives.

Zendesk, a provider of on-demand, help desk, customer services support network, has raised $60 million in new funding including $45 million in equity. Investors include new investors Index Ventures, GGV Capital, Goldman Sachs and existing investors Charles River Ventures, Benchmark Capital and Matrix Partners. The San Francisco-based company also secured $15 million in debt from Silicon Valley Bank. Zendesk has now raised more than $80 million in total funding since it was founded in 2007. CEO Mikkel Svane told peHUB in an email that the conmpany doesn’t have any acquisitions planned. “But we are focusing heavily on attracting the right talent and DNA to the company. We need a bigger pile of chips on the table to continue to execute at the pace we’re executing,” he said.

Adelphic Mobile today launched its intelligent Predictive Data Platform to allow companies to buy and sell mobile advertising at scale and optimize those campaigns. The company, which raised $2 million in seed funding from Matrix Partners, is founded by mobile advertising vets Jennifer Lum and Changfeng Wang. PRESS RELEASE Adelphic Mobile Introduces Intelligent Predictive Data PlatformTM for [...]