regex: if a line doesn't start with a particular string, add it as prefix

I've this text:

£££££Ciao a tutti§§§§§,§§§§§2009§§§§§,§§§§§8§§§§§
£££££Il mio nome è Geltry§§§§§,§§§§§2009§§§§§,§§§§§6§§§§§
Bla bla bla§§§§§,§§§§§2010§§§§§,§§§§§7§§§§§
£££££Le amiche della sposa§§§§§,§§§§§2011§§§§§,§§§§§3§§§§§

With TextCrawler I find all the lines that have not £££££ as a prefix, so:

^((?!£££££).)*$

What I should write as replacement?

Reg Ex: ^((?!£££££).)*$
Replacement: ?  <-- what write here?

to have:

£££££Ciao a tutti§§§§§,§§§§§2009§§§§§,§§§§§8§§§§§
£££££Il mio nome è Geltry§§§§§,§§§§§2009§§§§§,§§§§§6§§§§§
£££££Bla bla bla§§§§§,§§§§§2010§§§§§,§§§§§7§§§§§
£££££Le amiche della sposa§§§§§,§§§§§2011§§§§§,§§§§§3§§§§§