John Sonnier

John Sonnier

Managing Director, Head of Life Sciences

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About John

John Sonnier is a managing director for William Blair based in the firm’s Chicago office. He originally joined William Blair in 2005. Prior to William Blair, he worked for Prudential, Vector Securities International, Baxter International, and Johnson & Johnson.

Board Membership

Lake County Community Foundation

Notable Transactions

$287,510,350

Follow-on Offering

$103,500,000

Follow-on Offering

$40,266,204

PIPE

$163,854,204

Follow-on Offering

$56,525,000

Follow-on Offering

$80,500,000

Follow-On Offering

$128,800,000

Follow-on Offering

$120,750,000

Follow-on Offering

$209,299,994

Initial Public Offering

$110,500,000

Initial Public Offering

$143,750,000

Initial Public Offering

$114,999,888

Follow-on Offering

Rigorous pursuit of your success. Every transaction. Every time.

Our investment bankers are 100 percent committed to your organization’s sustained success. By drawing on our deep industry and product experience as well as our dedicated global resources, we provide advisory and financing services that allow you to capitalize on today’s opportunities and anticipate tomorrow’s challenges.

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Biopharma

The rapid and cost-effective development of innovative therapeutics and treatments is critical not just to public health, but to the functioning of society and economic activity. Leading drug developers, as well as their partners across the research, development, and manufacturing value chain, count on William Blair’s deep expertise in biopharma’s capital-raising and deal-making landscape.

More about our biopharma expertise
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Medical Technology

William Blair’s Medical Technology team works with many of the world’s most innovative medical technology companies to help transform their growth trajectory through capital access and M&A partnerships. By combining deep expertise in the mega trends driving life science and medical product innovation and our knowledge of the regulatory and reimbursement environment, we deliver trusted advice and outstanding execution for market-leading companies and financial sponsors.

Learn more about our medical technology expertise
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About William Blair

William Blair is a premier global boutique with expertise in investment banking, investment management, and private wealth management. We provide advisory services, strategies, and solutions to meet our clients’ evolving needs. As an independent and employee-owned firm, together with our strategic partners, we operate in more than 20 offices worldwide.*

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1935

Year William Blair was founded

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1,850+

Employees worldwide

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142 billion+

Client assets

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89 Years

Independent and employee-owned

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20+

Offices worldwide

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~650

Companies under coverage

As of March 31, 2024
*Includes strategic partnerships with Allier Capital, BDA Partners, and Poalim Capital Markets.

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