Yen’s strength appears to have a real demand - BBH

Research Team at BBH, suggests that the Japanese officials may be tempted to intervene, but perhaps the only thing worse than intervention is failed intervention. 

Key Quotes

“The track record of unilateral Japanese intervention is nothing to write home about.  Although speculators have been buyers of yen (judging from the futures market), and foreigners have been buying Japanese government bonds (weekly MOF data), the yen's strength appears to have a real demand as well. 

It appears to be coming from Japanese investors themselves, repatriating foreign earnings and hedging foreign portfolio investment.  There have been some suggestions that Japanese corporates have begun hedging their foreign retained earnings.  They had been earning superior yields, which have been offset and more by the yen's strength.”