1. Includes 488 shares acquired under a dividend reinvestment plan.

2. This transaction was executed at multiple prices ranging from $185.51 to $185.96. The price reported above reflects the weighted average sale price. The reporting person hereby undertakes to provide upon request to the SEC staff, Illinois Tool Works Inc. or a shareholder of Illinois Tool Works Inc. full information regarding the number of shares and prices at which the transaction was effected.

3. Shares of common stock allocated to the reporting person's account in the Illinois Tool Works Inc. Savings & Investment Plan. Information reported as of August 3, 2020.

4. Options vested in four (4) equal annual installments beginning one year from date of grant.