$_ = 'some random text<B><P ALIGN=CENTER>My Text I want to grab 1</B><
+/FONT><p>some of stuff<B><P ALIGN=CENTER>My Text I want to grab 2</B>
+</FONT> some other random text<B><P ALIGN=CENTER>My Text I want to gr
+ab 3</B></FONT>';
my @wants = /<B><P ALIGN\=CENTER>(.+?)<\/B><\/FONT>/g;
print "$_\n" for @wants;
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Note non-greedy match.