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• Calix January 27 , 2021 Fellow Calix stockholders : The profound changes we have all experienced in 2020 remained in full effect in the fourth quarter . The coronavirus pandemic continues to rage and evolve around the globe . While we are encouraged by the new administration's focus on ending the pandemic , even the best plan with the best execution will take time to show results . We believe it is time for all of us to come together , fight this pandemic and heal our economy . Until we do so , significant uncertainty will remain . As we have discussed , the two secular disruptions moving through the communications industry have been accelerated by the pandemic . In 2020 we saw a realignment of work , education and entertainment , and we expect these trends will continue . Furthermore , we expect a significant portion of these new behaviors will remain , albeit in a hybrid form , after the pandemic has abated . This simply means for Calix , the future is sooner ! As a company , we remain focused on the health and welfare of our employees and their families . We are doing all we can to support them as they work through these challenging times . In our view , only by remaining healthy and strong can we continue to serve the needs of our customers . We believe focusing on our culture yields results , and in the fourth quarter we actually received awards for our diversity , culture and leadership . While Carl Russo will continue as our CEO , today we announced that Michael Weening has been promoted to President and Chief Operating Officer . Since joining four years ago , Michael has played a significant role in transforming Calix into the All Platform leader . It is clear our team is core and central to achieving our mission , and we are committed to strengthening it each and every day . With service providers of all types responding to the increased demand for their services , the value of our All Platform offerings continue to resonate , and demand for our Revenue Edge and Intelligent Access Edge solutions continues to grow . In the fourth quarter of 2020 , we set new records for many metrics beginning with record quarterly revenue driven by strong demand and overperformance by our supply chain team . This record revenue performance was driven by the diversity of our products , services and customers as we saw growth across customers of all sizes . For the first time in our history , no customer accounted for greater than 10 % of revenue in the quarter , a fact that makes clear the difference between our old company and our new All Platform one . As our All Platform offerings continued their growth , we delivered record corporate gross margins . We maintained our disciplined operating expense investments as operating expenses increased at less than half the rate of our revenue growth compared to the year ago quarter . The combination of higher revenue , increased gross margin and disciplined operating expense investments led to record GAAP and non - GAAP net income per diluted common share and operating cash flow . We enter 2021 in the strongest financial position in our history and believe we are perfectly placed to execute on the opportunity ahead . 1