CITIBANK Plaza is more than 50 per cent let, with another 100,000 square feet ''under serious negotiation'' according to Mr Tong Chun-wan, director of Shine Hill Development. However, the space occupied by Citibank itself accounts for a large proportion of the 50 per cent take-up figure. Of the building's total space of 1.2 million sq ft, Citibank has bought 200,000 sq ft and is renting 100,000 sq ft at $50 per sq ft. The bank has rights to purchase another 50,000sq ft. However, Mr Tong said that the space occupied by Citibank was not directly comparable with that occupied by other tenants. ''In the case of the other tenants, the figures refer to lettable area whereas Citibank's portion does not,'' he said. Lettable area includes office space and communal areas. Mr Tong said that, in effect, of the 600,000 sq ft taken up, Citibank had slightly less than 300,000 sq ft. He denied rumours of rent-free periods of as much as a year being offered to tenants. The maximum rent-free period had been six months but was now limited to four months. The rent-free period had varied from three months to six months last year while tenants took time to fit out their premises, he added. Some larger tenants had up to six rent-free months last year, but this would not be the case this year. Rents which are about $42 per sq ft, were expected to go slightly higher. Mr Tong said rents varied a little, adding they were ''all in the 40s''. At the end of the third quarter of last year rents had been around $38-$39 per sq ft. The consultancy firm McKinsey was the most recent tenant to commit to space in the building, taking the 31st floor of Asia Pacific Financial Tower. Credit Lyonnais was another tenant to commit to space in the building recently, taking on about 7,000 sq ft. A specialised section of the Hongkong and Shanghai Bank has also taken on 7,000 sq ft. Hampton Winter and Glynn, a firm of solicitors was already in operation, occupying the 38th floor. Mr Tong said other interested parties were in the process of negotiation. He said the rent level and the rate of take-up were ''in line with the market''.