The number of lawsuits involving elderly residents has surged in urban Shanghai, especially disputes concerning money, division of property and second marriages.

The Shanghai Jing'an District People's Court received 654 cases involving seniors in the first nine months of this year, a nearly 50 percent increase from the same period last year, according to a court report issued ahead of Wednesday's Double Ninth Festival, a traditional celebration of the elderly.

Shanghai has more residents age 60 and older than any other Chinese city. The number reached 4.14 million last year, and accounted for nearly 30 percent of the total population.