This link:
http://www.privacyrights.org/fs/fs10-ssn.htm
has a lot of information about your rights and your SSN. Below is a part of this page.
>>>Do I have to provide my Social Security number to private businesses?
Usually you are not legally compelled to provide your Social Security number to private businesses -- including private health care providers and insurers -- unless you are involved in a transaction in which the Internal Revenue Service requires notification. (MediCal and Medicare are government health plans and can require a Social Security number.)
There is no law, however, that prevents businesses from requesting your SSN, and there are few restrictions on what businesses can do with it. But even though you are not required to disclose your SSN, the business does not have to provide you with service if you refuse to release it.
If a business insists on knowing your Social Security number when you cannot see a reason for it, speak to an administrator who may be authorized to make an exception or who may know that company policy does not require it. If the company will not allow you to use an alternate number, you may want to take your business elsewhere.
Credit card applications usually request Social Security numbers. Your number is used primarily to verify your identity in situations where you have the same or a similar name to others. Although most credit grantors will insist on having your SSN, you may be able to find a credit grantor who will provide you credit without knowing your SSN, especially if you are persistent and can provide other forms of identification. But such instances are rare.
In California, a new law restricts how certain businesses can display their customers' Social Security numbers. It does not restrict the collection of SSNs, however, and it does not affect government agencies. California Civil Code 1798.85 is being phased in from 2003 to 2005. Insurance companies will not be able to print the SSN on identification cards to be carried in the wallet. Customers of banks and investment companies cannot be required to transmit the SSN over the Internet when conducting business online, unless the number is encrypted. SSNs cannot be printed on documents sent through the mail, with some exceptions. The California Office of Privacy Protection provides a guide for businesses on "recommended practices" for using SSNs. It includes a description of the new law, www.privacy.ca.gov/recommendations/ssnrecommendations.pdf. The full text of the law is found on the state's official legislative web site, www.leginfo.ca.gov.
Should I provide my Social Security number over the Internet?
Many individuals now shop on the Internet. In some instances a commercial website might require your SSN, for example if you apply for a credit card online. We advise that you take extra precautions to determine that your personal data is transmitted securely and that it is stored safely by the online business.
Only conduct such transactions with known, reputable companies. Look for the closed padlock symbol on the bottom of the page. Read the company's privacy policy to learn how it safeguards your customer data. If necessary, call the company and talk to an individual who is knowledgeable about its security practices. Do not conduct business with the company if it does not appear to safeguard its customers' data adequately. For more online shopping tips, read the PRC's Fact Sheet number 23, www.privacyrights.org/fs/fs23-shopping.htm.
Be on the alert for unsolicited electronic mail messages in which your SSN and other personal information are requested. Many individuals report having received e-mail messages that appear to be from their Internet Service provider, for example AOL, or from a government agency like the Internal Revenue Service. The message typically states that the company or agency is updating its records and that it needs certain information from you, such as Social Security number. Do not respond to such messages. Even though they appear to be official, these messages and/or websites are a scam. No reputable company or government agency sends unsolicited e-mail messages to individuals in which sensitive personal data is sought in this manner.<<<