My website home page title is in the following format, Homepage | Title of the page | Companyname. But however in the google search, it shows differently and add automatically a prefix like below format, Companyname: Homepage | Title of the page
Why it appears like this? How can I remove the prefix Companyname: and keep it like exactly the title I have added for the page? Homepage | Title of the page | Companyname
Google rewrites page titles it doesn't like. You won't be able to force it to give the exact one specified.
In this moz.com article, they reckon 58% of pages they looked at had been re-written.
I'd give the whole article a read, but in your case the likely thing triggering the re-write is the following:
Google seems to be taking a dim view of pipes (|) in general with this new update. In our data set, over 10,000 titles with pipes were rewritten, and nearly 6,000 of those were below the pixel-width limit.
Pipes or vertical bars are used by Google SE to split and then reformulate the title. This is based on my own trials.
If you don't want this then don't use pipes. Try dashes. In the end, however, GSE is free to reformat it to suit. Whatever you do is a suggestion to it.
