John Sonnier

John Sonnier

Managing Director, Head of Biopharma

About Mr. Sonnier

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

$100,280,000

Follow-on Offering

$345,000,000

Initial Public Offering

$82,500,000

Initial Public Offering

$516,000,000

has been acquired by

$115,000,000

Private Placement

$224,000,000

Initial Public Offering

$46,750,000

Follow-on Offering

$632,500,000

Follow-on Offering

$258,750,000

Follow-on Offering

$115,920,000

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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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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Year William Blair was founded

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+1,800

Employees worldwide

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+136 billion

Client assets

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86 Years

Independent and employee-owned

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20+

Offices worldwide

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~700

Companies Under Coverage

As of September 30, 2021
*Includes strategic partnerships with Allier Capital, BDA Partners, and Poalim Capital Markets.

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