The U.S. health technology firm, which has on its board Pearson’s former chief executive Marjorie Scardino and former Sanofi chief executive Chris Viehbacher, said its listing valued the firm at£364 million ($578 million).
The offer price was set at £1.60 per share. Last month PureTech said it hoped to bring in $160 million.
The group specializes in building a portfolio of early-stage science and technology ideas in the healthcare sector, typically from academia and nurturing them into commercially viable businesses.
The focus is particularly on the convergence of new technologies in healthcare. Many traditional tech companies, such as Google and Apple, are now investing in health, leading to new opportunities for merging different approaches to treating patients.
The move to list in London follows a similar decision by California-based biotech firm Verseon to raise $100 million in London earlier this year.
Allied Minds also floated in London a year ago. It raised about £76 million ($120.6 million) in a listing priced at £1.90 a share, giving the company a market value of nearly £400 million at the time. The shares trade around £5.50 today.
($1 = £0.6303)