The Company and Nature of Business

12 Months Ended

Dec. 31, 2020

Organization, Consolidation and Presentation of Financial Statements [Abstract]

The Company and Nature of Business

The Company and Nature of Business

SI-BONE, Inc. (the “Company”) was incorporated in the state of Delaware on March 18, 2008 and is headquartered in Santa Clara, California. The Company is a medical device company that has pioneered a proprietary minimally invasive surgical implant system to fuse the sacroiliac joint for treatment of the most common types of sacroiliac joint disorders that cause lower back pain. The Company introduced its primary product, the iFuse Implant System, or iFuse, in 2009 in the U.S., in 2010 in certain countries in the European Union, and in 2015 in certain countries in the rest of the world.

Public Offerings of Common Stock

In October 2018, the Company completed its initial public offering (“IPO”) by issuing 8,280,000 shares of common stock, at an offering price of $15.00 per share for net proceeds of $113.4 million to the Company, net of underwriting discounts and commissions and offering costs.

In January 2020, the Company received $50.0 million net proceeds, after deducting the underwriting discounts and commissions, from its public offering of 4,300,000 shares of the Company's common stock at a public offering price of $21.50 per share, of which 2,490,053 shares were offered and sold by the Company. Further, in February 2020, the underwriters fully exercised its option to purchase 645,000 shares of the Company's common stock at a public offering price of $21.50 per share for an additional net proceeds of $13.0 million to the Company, after deducting the underwriting discounts and commissions. The total public offering costs incurred in connection with the follow-on offering were allocated based on the gross proceeds received by the Company and the other selling shareholders on a pro-rated basis. Public offering cost of $0.4 million allocated to selling of shares by the Company was charged against the gross proceeds received from the follow-on offering. Public offering costs of $0.2 million allocated to selling of shares by the selling shareholders was recognized as transaction costs within general and administrative expenses on the consolidated statements of operations in the year ended December 31, 2020.

In October 2020, the Company received $71.6 million of net proceeds from its second follow-on public offering of 3,000,000 shares of the Company's common stock, and the exercise of underwriter's option to purchase from the Company an additional 478,507 shares of the Company's common stock, at a public offering price of $22.00 per share. In addition to the shares sold by the Company in the second follow-on offering, in October 2020, the selling stockholder sold 190,053 shares of the Company's common stock previously held by the selling stockholder at a price to the public of $22.00 per share. The Company did not receive any proceeds from the sale by the selling stockholder.