Using class in H1 tag

SEO agency says do not use class in H1 tag

[pankajj]

The way we are displaying our H1 tags on page html is <h1 class="section_title">Product Orientation: Overview</h1>. Our SEO agency is of the opinion that we should take away the class from the html and instead have our H1 class defined in global css.
Does having a class inside the H1 tag reduces the seo weight?

[trillianjedi]

Does having a class inside the H1 tag reduces the seo weight?

Not as far as I've ever been able to detect.

instead have our H1 class defined in global css.

I think that's a sensible idea anyway. Keeping style information outside of the markup and content is generally a good thing. Taking this approach with all markup will lead to lighter weight pages and more content, less markup.

Are you sure they were specifically referring to SEO, or was this just general advice/suggestions?

[pankajj]

Our agency is specifically refering to SEO. The issue here is that our website has more than 20000 web pages and somewhere H1 could have been used without a class and at some places with call in the tag. The agency is pressing on that removing the class from within the H1 tag will increase its SEO weight

[trillianjedi]

Well, perhaps they have some data from those differences in pages that indicate to them there's an effect.

It certainly won't do you any harm to do as they suggest.

Is there a reason you don't want to do it ?

[pankajj]

The agency does not have any data of those difference in pages. To get this change done, will require to invest good engineering time to first investigate, list down pages and then make the change. Our entire portal is dynamic & xml driven where we have placeholders for each section, driven from database and all pages are rendered in html format to users and search crawlers

[g1smd]

You only need class names on elements that are going to be styled different from the default.

I don't see a lot of SEO value in the change, but I am all for simpler markup, especially as a bandwidth saving exercise.