Hong Kong market counter-intervention against the double play (1998)

Between 14 and 28 August 1998, the Hong Kong government used the Exchange Fund to buy HKD 118 billion of local equities and futures during pressure on the currency and stock markets. Officials described the cross-market strategy they opposed as a 'double market play': speculators sold Hong Kong dollars while holding short equity-index positions, seeking to profit from the interest-rate rise produced by the currency board's defence. The mechanism is demonstrable. Coordination by named funds and manipulative intent were alleged by the authorities, not established through adjudication or public position-level evidence.

The alleged double play

Hong Kong's linked exchange-rate system converted sales of Hong Kong dollars into monetary contraction and higher short-term interest rates. During the Asian Financial Crisis, that adjustment could depress equity prices even if the peg survived. A trader positioned short in the stock-index futures market could therefore benefit from the currency defence without successfully breaking the peg.

The authorities argued that unusually heavy currency sales and futures positioning in August 1998 reflected this linked strategy. Later research by Sujit Chakravorti and Subir Lall showed how such a trade could operate, while Charles Goodhart and Lu Dai reconstructed the Hong Kong episode. Neither body of work turns the government's allegation into proof that specific hedge funds coordinated an unlawful attack.

Counter-intervention

The government entered the equity and futures markets on 14 August. Purchases continued through the August futures settlement on 28 August and produced an equity portfolio of about HKD 118 billion. The stated purpose was to remove the profit mechanism behind the alleged double play and protect market integrity, not to replace the currency board with discretionary exchange-rate management.

The market operation must be separated from the seven technical measures announced on 5 September. Those reforms strengthened the currency board by, among other changes, providing a convertibility undertaking on the weak side of the linked rate and adjusting liquidity arrangements. Securities-market changes addressing short selling and settlement were another distinct part of the response.

Outcome and assessment

The peg remained intact and the immediate cross-market pressure receded. Those facts establish operational survival, not exclusive causation. Russia's default changed global risk appetite during the same month. Regional conditions, interest-rate expectations and Hong Kong's recession also shaped prices. An event study found market effects around the intervention, but it did not identify every trader or eliminate those confounders.

The equity portfolio was not immediately liquidated. Exchange Fund Investment Limited was created to manage it, and part was transferred to the public through the Tracker Fund of Hong Kong from 1999. Later disposal and portfolio value are separate tests from the intervention's success in August 1998.

The case demonstrates defensive statecraft inside markets. Hong Kong used public balance-sheet capacity to challenge the payoff structure of a private trade, then changed the rules governing the linked system. It succeeded most clearly against three defined objectives: the peg survived, the August trade was disrupted and the currency-board framework was hardened. Whether direct public equity purchases should be generalised as a defensive instrument remains contested.

See also

Asian Financial Crisis and regional financial resilience, 1997-1998 · Currency-peg attack · FX shorting and speculative attack · Market-based warfare · Hong Kong Monetary Authority · Black Wednesday and the ERM crisis, 1992 · Financial warfare

Sources

1. Hong Kong Monetary Authority, *Annual Report 1998*.
2. Joseph Yam, 'Why We Intervened', HKMA Quarterly Bulletin (November 1998).
3. Hong Kong Monetary Authority, 'Strengthening of Currency Board Arrangements in Hong Kong', HKMA Quarterly Bulletin (November 1998).
4. Charles Goodhart and Lu Dai, *Intervention to Save Hong Kong: The Authorities' Counter-Speculation in Financial Markets* (Oxford University Press, 2003).
5. Sujit Chakravorti and Subir Lall, 'The Double Play: Simultaneous Speculative Attacks on Currency and Equity Markets', Federal Reserve Bank of Chicago Working Paper 2000-17.
6. International Monetary Fund, *International Capital Markets: Developments, Prospects, and Key Policy Issues* (1999).
7. Bank for International Settlements, *69th Annual Report*, chapter III (1999).
8. Yuli Su, Yewmun Yip and Rickie W. Wong, 'The impact of government intervention on stock returns: Evidence from Hong Kong'00101-6), International Review of Economics and Finance 11, no. 3 (2002): 277-297.