Will one line of duplicate content drag down my landing page?

[Ticket_King]

I am using copyscape to check for duplicate content on my landing pages. I found three sites that have the exact same sentence as mine, on a page that I rank well for on one of two key terms related to the product. The sentence is not essential to my product page.  Do I risk losing page one rank on a key search term when I remove that sentence on my site, in hopes of possibly improving the page on the second key search term?

Do I leave it alone? This is an older "template" site with very little that I can do SEO-wise, and I have managed to get a few key prodcut landing pages on page one of Google.  It has seen a drop in rank on many landing pages post-panda, and I'm doing my best to clean up what I can.  Do I leave well enough alone for a page one rank on one term, or swap out that sentence in hopes of getting better rank on two keywords?

[RyanKent]

Generally speaking, one line of duplicate content will not negatively impact the SERP performance of a web page.

A couple instances where a page could be affected:

• the duplicated sentence is the first sentence of the article

• the article is very short (i.e. <100 words)

It is common practice for a single sentence to be duplicated elsewhere.

[BenFox]

I agree with Ryan.

No. It's not going to hurt you.

[DesignbysoapLtd]

Completely agree with Ryan - assuming it's not the first sentence or an extremely short article you're absolutely fine.

Duplicate lines are very common - most notably as a quote (think how many times you see this in news publications).