This is an issue of what's known as "ex post facto punishment." and it's an issue the courts have wrestled with for awhile.

As of now, public access to sex offender registration data under PC 290.4 is permitted even if the offense occurred prior to the 2005 internet requirement. However, there is a case called <i>People v. Milligan</i> currently winding it's way through the California Courts that may be of interest to you. In <i>Milligan</i>, a person convicted of a sex offense in 1987 is challenging the various additions to the registration laws since his conviction.

One cannot predict how the California courts will rule, but you should know that there is case law from the U.S. Supreme Court (Smith v. Doe), that permits internet notification for cases that pre-date the internet.

If you're interested in reading more google:

People v. Milligan, 166 Cal. App. 4th 1208 (pending re-hearing)
Smith v. Doe, 538 U.S. 84

If you can't find the cases, contact me through this site and I will send them to you.

Good luck.

Instead of waiting for a case to make its way through the Court of Appeals. you may be able to get your mug off the Internet much sooner.

You can ask to be taken off the California sex offender website if your only registrable offense was:
- Sexual battery by restraint (Penal Code § 243.4(a)
- Annoying or molesting a child, under Penal Code § 647.6, or former section 647a
- Any offense which did not involve penetration or oral copulation, where the victim the victim was your child, stepchild, grandchild, or sibling, and you successfully completed probation.

If you're eligible, you have to file a specific form with the Department of Justice to be removed from the website. I've posted a link at the end of this answer.

In addition, if you were convicted of a misdemeanor violation of Penal Code §647.6, you may be able to obtain a Certificate of Rehabilitation. which would relieve you from registration altogether.

Both California and Federal courts have consistently held that sex offender registration does not constitute punishment, so ex post facto principles do not apply. That includes the Smith v. Doe case mentioned in another answer. The California Milligan case cannot be used as legal authority because a rehearing was granted.