You will be given a definition of a task first, then some input of the task.
In this task, you are given a summary for US Congressional and California state bill, your task is to generate a Title for this bill. The preferred titles are under forty words and mention the purpose of the bill.

Narrowing Exceptions for Withholding Taxes Act of 2012 - Amends the Internal Revenue Code and title II (Old-Age, Survivors, and Disability Insurance Benefits) of the Social Security Act to require a shareholder of a subchapter S corporation engaged in a professional service business to include all items of income or loss attributable to such business in determining such shareholder's net earnings from self-employment for purposes of computing employment tax liability.

Defines a "professional service business" as any trade or business substantially all of the activities of which involve providing services in the fields of health, law, lobbying, engineering, architecture, accounting, actuarial science, performing arts, consulting, athletics, investment advice or management, or brokerage services.
Output:
To amend the Internal Revenue Code of 1986 and the Social Security Act to provide for employment tax treatment of professional service businesses.