Tim Cook: "Our industry has lost a pioneer."
"Our industry has lost a pioneer and our world has lost a force for good. We send our deepest condolences to Paul’s friends, the Allen family and everyone at Microsoft."
Apple CEO Tim Cook on Twitter
Satya Nadella: "I have learned so much from him."
"Paul Allen’s contributions to our company, our industry and to our community are indispensable. As co-founder of Microsoft, in his own quiet and persistent way, he created magical products, experiences and institutions, and in doing so, he changed the world."
"I have learned so much from him — his inquisitiveness, curiosity and push for high standards is something that will continue to inspire me and all of us at Microsoft. Our hearts are with Paul’s family and loved ones. Rest in peace."
Microsoft CEO Satya Nadella on LinkedIn
Sundar Pichai: "We lost a great technology pioneer."
"We lost a great technology pioneer today - thank you Paul Allen for your immense contributions to the world through your work and your philanthropy. Thoughts are with his family and the entire Microsoft community."
Google CEO Sundar Pichai on Twitter
Bill Gates: "I am heartbroken."
"I am heartbroken by the passing of one of my oldest and dearest friends, Paul Allen. From our early days together at Lakeside School, through our partnership in the creation of Microsoft, to some of our joint philanthropic projects over the years, Paul was a true partner and dear friend. Personal computing would not have existed without him.
"But Paul wasn't content with starting one company. He channeled his intellect and compassion into a second act focused on improving people's lives and strengthening communities in Seattle and around the world. He was fond of saying, 'If it has the potential to do good, then we should do it.' That's the kind of person he was.
"Paul loved life and those around him, and we all cherished him in return. He deserved much more time, but his contributions to the world of technology and philanthropy will live on for generations to come. I will miss him tremendously."
Microsoft cofounder Bill Gates