In the event the ratings agency cut Greek long-term bond ratings by two notches to B from BB- and said that the outlook may bring a further weakening.

FORBES: Government Bonds Ignore Supply, Yields Fall

With loans trading higher in April, single-B loans again outperformed BB paper.

FORBES: Connect

Valuations here remain attractive relative to other quality buckets: spreads for BB and B bonds are still above their long-term historical levels (according to JP Morgan data) and issuers have plenty of cash and little debt maturing in the short term.

FORBES: Should Investors Still Go For High Yield?

The pattern was also clear in the new-issue market where single B clearing yields gapped out 13 bps versus those of BB loans, which remain in high demand not just from institutional loan accounts but banks and cross-over investors.

FORBES: Leveraged loans return 0.31% in November; YTD return is 8.8%

For higher credit quality issuers rated BB or higher, loan yields were effectively unchanged while single B rated borrowers paid roughly 50 bps more than they did in October.

FORBES: Leveraged Loan Market Analysis, December 2012

Loans to issuers rated BB printed in a 5-5.5% context, with single-B paper clearing at 6-7%, give or take.

FORBES: Connect