) --

Bank of America

(BAC) - Get Report

is one of three large cap banks that could face earnings pressure from the recent rally in 5 and 10-year U.S. Treasuries, while


(C) - Get Report


Huntington Bancshares

(HBAN) - Get Report

"seem least exposed near term" to negative impacts from the rally, according to a recent report from Deutsche Bank.

Yields on ten-year U.S. government bonds had fallen from 2.18% at the start of the second quarter to 1.58% as of Thursday afternoon, according to


data. Five-year Treasury yields fell from 1.01% to 0.66% over the same period.

The decline in interest rates threatens to pressure banks' net interest margins (NIM)--the difference between what it costs them to borrow and what they can earn on their loans, according to the report from analyst Matt O'Connor.

Banks holding high-yielding securities face a risk to their NIMs because as those securities mature, the banks are forced to reinvest at lower yields. Also at risk of lower NIMs are banks with a high concentration of bonds backed by pools of residential mortgages that are guaranteed by U.S. government agencies such as

Fannie Mae



Freddie Mac


. Those bonds, known as agency RMBS, tend to mature earlier than anticipated as borrowers take advantage of lower interest rates to refinance their mortgages.

According to O'Connor's research, however, all the banks that stand out as holding high yielding securities do not have a high concentration of agency RMBS. And the ones with a high concentration of agency RMBS don't own lots of high-yielding bonds. The translation, then is that (at least by these measures) no large cap banks face a high near-term threat to their NIMs. However, O'Connor singles out Citigroup and Huntington as being in particularly good shape by both of these measures relative to their peers.

Still, O'Connor singles out Bank of America,

Regions Financial

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SunTrust Banks

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as institutions he covers that could see a hit to their NIMs. That's because he believes they more than others have paid a premium for mortgage bonds, taking the extra cost out of their net interest income over time. However, if the bonds pay off more quickly than anticipated (due to refinancing at lower rates) that causes a hit to net interest income, as the premium must be amortized over a shorter period.

O'Connor isn't 100% sure which banks fall into this last category, however.


banks don't disclose how much (if any) bonds were purchased at a premium--so it's difficult to know for sure," he writes.


Written by Dan Freed in New York


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