According to Official Guinness Records,
The longest breakdance hand wave involved 7,014 participants and was achieved by Nana Mizuki fan club S.C. NANA NET (Japan) at the Tokyo Big Site, Tokyo, Japan, on 21 November 2009.
Nana Mizuki is a Japanese pop singer and voice actress. Her fan club members tried three record attempts at the concert. For this record attempt, 7,014 people in the audience successfully completed the hand wave.
For a complete list of 2009 records, please visit 2009 Guinness Records in Japan.