TORONTO — There are reports that Royal Bank of Canada (TSX:RY) has been served with a subpoena from U.S. state officials as part of their probe into the possible manipulation of a key benchmark used to set interest rates.

The Wall Street Journal and other business publication report the subpoenas were issued to nine banks, including RBC, in August and September, according to an unidentified person familiar with the investigation.

That brings to 16 the number of banks served with subpoenas, including seven that had become public earlier.

The U.S. investigation by the New York and Connecticut attorneys general is part of a wider probe in several countries that stems from a major U.K. bank's admission that it had provided false information used to set the LIBOR rate.

RBC is Canada's largest bank, with operations in major financial centres around the world including London.

The bank said last summer that it followed the rules in submitting information for compiling the London Interbank Offered Rate, which is used widely as a benchmark to set interest rates on business and consumer debts.

The rate is set by gathering information from a small number of large banks, using a system that's intended to prevent any one member of the group from manipulating the rate.

Questions about how LIBOR is operated arose after Barclays Bank agreed to pay a record $450 million fine to settle allegations its traders had manipulated submissions to LIBOR.

While Barclays actions by themselves were probably insufficient to affect LIBOR, there authorities in Britain and elsewhere have launched probes to see if it was a more widespread problem.

Canada's competition bureau and other Canadian regulatory bodies launched their own probes in light of the Barclay's revelations but there have been no allegations levelled against RBC.

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  • Worst: CIBC - 722

    Number represents overall score out of 1,000.<br> <br> Source: <a href="http://www.jdpower.com/content/press-release/u3sOSZa/2012-canadian-retail-banking-customer-satisfaction-study.htm" target="_hplink">J.D. Power Canadian Retail Banking Customer Satisfaction Survey</a>

  • 4: Scotiabank - 740

    Number represents overall score out of 1,000.<br> <br> Source: <a href="http://www.jdpower.com/content/press-release/u3sOSZa/2012-canadian-retail-banking-customer-satisfaction-study.htm" target="_hplink">J.D. Power Canadian Retail Banking Customer Satisfaction Survey</a>

  • 3: Bank of Montreal - 743

    Number represents overall score out of 1,000.<br> <br> Source: <a href="http://www.jdpower.com/content/press-release/u3sOSZa/2012-canadian-retail-banking-customer-satisfaction-study.htm" target="_hplink">J.D. Power Canadian Retail Banking Customer Satisfaction Survey</a>

  • 2. Royal Bank of Canada - 751

    Number represents overall score out of 1,000.<br> <br> Source: <a href="http://www.jdpower.com/content/press-release/u3sOSZa/2012-canadian-retail-banking-customer-satisfaction-study.htm" target="_hplink">J.D. Power Canadian Retail Banking Customer Satisfaction Survey</a>

  • Best: TD Bank - 769

    Number represents overall score out of 1,000.<br> <br> Source: <a href="http://www.jdpower.com/content/press-release/u3sOSZa/2012-canadian-retail-banking-customer-satisfaction-study.htm" target="_hplink">J.D. Power Canadian Retail Banking Customer Satisfaction Survey</a>



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  • What Canadian Banks' Profits Can Buy You

    Canada's Big Five banks recorded a total profit of $7.5 billion in the three months ending July 31, 2012. Here's what that money can buy you.

  • Tuition for 1,397,689 undergrads

    The average undergraduate tuition in Canada today <a href="http://www.statcan.gc.ca/daily-quotidien/110916/dq110916b-eng.htm" target="_hplink">stands at $5,366</a>.

  • 5 billion fees for using another bank's machine

    Banks can charge up to $2 or even $2.50 for non-customers using their machines, but we've used the more common $1.50 charge for this calculation.

  • 1.36 billion fresh whole chickens

    The going retail rate for a whole chicken in Canadian supermarkets <a href="http://www3.agr.gc.ca/apps/aimis-simia/rp/index-eng.cfm?report_format_type_code=21&action=gR&signature=DE08B1F45FFD7EDA1F7CEEA304E235E2&pdctc=&r=116&pTpl=1&btnDownload=View" target="_hplink">was $5.52 in June of 2012</a>.

  • 2.5 billion rides on Toronto's streetcar

    The cash fare rate on the TTC is $3.

  • 1,978,891,820 poutines at Harvey's

    Assuming a retail price of $3.79 each.

  • 1.25 million 1978 Darth Vader figurines

    They go <a href="http://actionfigures.about.com/od/historyofactionfigures/tp/top_5_starwars.htm" target="_hplink">for about $6,000 each these days</a>.

  • The average annual salary of 163,043 Canadians

    The average salary in Canada is <a href="http://www.workopolis.com/content/advice/article/1821-how-much-money-are-we-earning-the-average-canadian-wages-right-now" target="_hplink">around $46,000</a>.

  • 4.54 billion medium-sized double-doubles at Timmies

    Assuming a pre-tax price of $1.65 per cup.

  • 7,500 performances by Sting at your birthday party

    It's estimated the singer <a href="http://www.thestar.com/news/gta/article/1079200--sting-plays-toronto-woman-s-45th-birthday-bash" target="_hplink">charges $1 million per performance</a>.

  • 468,896 Honda Civics

    The basic model at the suggested retail price of $15,995.

  • 48 trips to the moon

    British company Excalibur Almaz is <a href="http://www.huffingtonpost.com/2012/06/22/excalibur-almaz-tickets-moon-photos_n_1619761.html" target="_hplink">selling tickets for trips to the moon at a cool $155 million</a>.

  • The entire economy of the Bahamas

    The Bahamas <a href="http://en.wikipedia.org/wiki/List_of_countries_by_GDP_(nominal)" target="_hplink">produced $7.7 billion in wealth in 2011</a>, slightly more than Canadian banks' $7.5 billion in profits in a three-month period.