According to The Telegraph

Heidi Allen, Anna Soubry and Sarah Wollaston are said to have quit the party.

They are believed to join up with the Independent Group and that makes the total number there to be 11 lawmakers. The pound falls further to a session low with cable touching 1.3012 now as markets are digesting the news.

Just be wary of the potential for further resignations as that will impact the pound more. As it stands, the three resignations here will do little to change the Brexit deal vote if we do come to that. But keep in mind:

As for impact to the pound, more talks of further resignations will be a pound negative as it reduces May's majority in parliament and could prompt worries about the outcome of future motions/votes when put a test at the Commons.

Currently, with DUP support, May commands a support of 327 MPs but the resignation here would reduce that to just 324 MPs. Counting out the speaker, a majority support in parliament is 322 MPs so this is bringing us closer to that tipping point on the scale.