Google has added a new option for verifying site ownership. The new method requires you to place a specific <meta> tag in the source code of your home page. As per Vanessa Fox of Google Engineering, many features are available only to site owners only. At least , as per now.
This new method comes as a boon for site owners who can't upload files or specify names for files. To verify using the <meta> tag, simply click the Verify link for your site, choose Add a meta tag as the verification option, and then copy the tag provided to the <head> section of your home page. Click here to know how to use this method.
Vanessa has also clarified some important questions.
I have a blog, and anyone can post comments. If they post this meta tag int a comment, can they can claim ownership of my site?
No. We look for this meta tag in the home page of your site, only in the first section and before the first . If your home page is editable (for instance, your site is a wiki-like site or a blog with comments or has a guest book), someone can add this meta tag to the editable section of your page, but cannot claim that they own it.
From this unique string, can someone determine my email address or identity?
Short answer, no. Long answer, we use a hashing scheme to compute the contents of the meta tag. Hashes cannot be "decrypted" back into the message.
Can the meta tag contents be cracked through a dictionary attack?
To reduce the risk of dictionary attacks, we use a random sequence of bytes (called salt) as a seed to the hash function. This makes dictionary attacks much more difficult.
What if my home page is not HTML content?
This method may not work for you. You must have a section in order to be able to verify using this approach. Instead, try uploading a verification file to verify ownership of your site.