• Dealers report one buyer of 2-week expiry 152.00 JPY call/USD put option on USD 500 million Wednesday

• Given that the average FX option trade is USD 30 million, this is a notably large trade. Implied vol was 12.0

• Option will increase in value if spot lower/implied vol higher and end in profit if spot below strike at expiry

• If spot was 155.90 when struck, the premium would have been around 28 JPY pips or 0.18% of USD

• The latest suspected intervention saw USD/JPY drop 157.82-155.00 in Asia - options right to stay cautious

• Related comment - Japans costly JPY defence can only buy time (Richard Pace is a Reuters market analyst. The views expressed are his own)