Free Writing Prospectus
Filed Pursuant to Rule 433
Registration No. 333-169119
January 4, 2013
Barclays Capital Inc., and its affiliates, and BlackRock Investments, LLC, and its
affiliates, do not provide tax advice, and nothing contained herein should be construed to be tax advice. Please be advised that any discussion of U.S. tax matters contained herein (including any attachments): (i) is not intended or written to be
used, and cannot be used, by you for the purpose of avoiding U.S. tax-related penalties, and (ii) was written to support the promotion of marketing of the transactions or other matters addressed herein. Accordingly, you should seek advice based on
your particular circumstances from an independent tax advisor. Investing in MLPs The iPath® S&P MLP ETN iPath® Exchange Traded Notes BARCLAYS
iPath ® IMLP key facts iPath® S&P MLP Exchange Traded Notes: Listed on NYSE
Arca (ticker: IMLP) Tracks the S&P MLP Index Offers exposure to leading US public partnerships focused on energy and utilities Yearly fee: 0.80%1 Designed to pay quarterly coupons2 Daily redemption to Barclays Bank PLC as issuer 3 Your broker is
expected to issue a form 1099 with respect to the ETNs, not a Form K-1 1. The daily fee value on any calendar day is equal to (1) the ETN Current Value on such calendar day times (2) 0.80% divided by (3) 365. Because the daily fee value is
calculated and subtracted from the closing indicative value on a daily basis, the net effect of the fee accumulates over time and is subtracted at the rate of 0.80% per year. 2. Comprised of the distributions that would be received by a hypothetical
holder of the shares in the Index, minus accrued fees. See relevant prospectus. 3. Subject to minimum size of 50,000 units and timing limitations as prescribed by prospectus Page 2 BARCLAYS
iPath® Platform iPath ® Institutional Wealth Management Retail Efficient access
to futures markets FX, Commodity, Emerging Markets Access to hard-to-reach asset classes Tradable index-linked structured and Volatility use investment Easy to investment Cost efficient Leveraged and inverse exposures Short-term views /cash
management Liquidity and ease of exit US Listed iPath ETNs Asset Classes Billion dollars in total iPath® trading since launch Percent market share of US ETNs $10,000,000,000 Peak Notional Outstanding (03 / 2011) Sources: Bloomberg, 12/31/12 Page
3 73 10 5 35 731 BARCLAYS
iPath ® Master Limited Partnerships (MLPs) MLPs are publicly traded limited
partnerships Trade on an exchange like common stocks Generally considered partnerships for US federal income tax purposes MLPs generally own energy infrastructures, such as crude oil or natural gas pipelines Establish long term contracts with energy
companies for use of the infrastructure Aim to generate consistent fee-based revenue Historically, demand for use of energy infrastructure has had low correlation with commodity prices MLPs are hybrid securities - historically competitive yield and
price appreciation Yield is historically comparable to high yield credit Price appreciation is historically comparable to equity markets Historically, credit (yield spread) dominates short-term horizon, while growth determines longer term
performance MLPs are a growing asset class Market capitalization increased from $8 billion in 1995 to $321 billion in 20121 1. Source: Factset, 12/29/1995 - 12/31/2012. Page 4 BARCLAYS
iPath ® BARCLAYS The S&P MLP Index The S&P MLP Index (the
“Index”) is a benchmark index tracking leading US Master Limited Partnerships Key features: since index launch date1 1. Historical Historical annualized price returns: 4.4% per annum 2 Returns Outperforming other equity benchmarks annum 1
2. Income Historical average dividend yield per is 7.0% and potentially more attractive on a tax-adjusted basis Revenues generally consistent throughout business cycles, because dependent on long-term contracts 3. Diversification Typically low
correlation to equity and bond markets over the long term Typically low correlation to underlying commodity, because supported by fee-based businesses The performance of the Index is subject to certain risks. See page 12 for more information. 1.
Source: Bloomberg, for the period 9/6/2007 – 12/31/2012. Page 5 2. Outerformance relative to the S&P500® (annualized returns -0.7% over the same period). Source: ibid.
1. Historical index returns S&P MLP Index Alerian MLP Index1 S&P 500®
Annualized Price Returns 4.4% 4.4% -0.7% Annualized Volatility 24.5% 24.3% 25.9% Average Annual Yield 7.0% 7.0% 2.2% Correlation vs. S&P 500® Index 69.1% 69.3% 100.0% Returns over Volatility Ratio 0.18 0.18 -0.03 Source: Bloomberg. Data
shows calculations for the period 9/6/2007 – 12/31/2012. 1. The Alerian MLP index is an index tracking the performance of the 50 most prominent energy MLPs. Index returns are for illustrative purposes only. Index performance returns do not
reflect any investor fees, transactions costs and expenses. Page 6 Indexes are unmanaged and one cannot invest directly in an Index. Past performance is not indicative of future results. 140 S&P MLP Index 130 Alerian MLP Index 120 ®
S&P500 110 100 90 80 70 60 50 40 Sep-07 Mar-08 Sep-08 Mar-09 Sep-09 Mar-10 Sep-10 Mar-11 Sep-11 Mar-12 Sep-12 iPath ® BARCLAYS
iPath ® BARCLAYS 2. Quarterly distributions Historically, distribution from the
S&P MLP Index constituents have been: Significantly higher than dividends from securities in the S&P 500® Consistent throughout the business cycle Source: Bloomberg 9/30/2007 – 12/31/2012. Page 7 Past performance does not guarantee
future results. 0 . 0 . . 1 . 1 2 . . 2 . 3 0% 5% 0% 5% 0% 5% 0% Q4 2007 Q1 2008 Q2 2008 Q3 2008 Q4 2008 Q1 2009 Q2 2009 Q3 2009 Q4 2009 Q1 2010 Q2 2010 Q3 2010 Q4 2010 Q1 2011 Q2 2011 Q3 2011 S&PS&P Q4 2011 500 Alerian MLP ® MLP Q1 2012
Index Q2 2012 Index TR Q3 2012 Q4 2012
iPath ® BARCLAYS 3. Diversification S&P MLP TR Index Correlation1 with
Benchmarks Henry Hub WTI Cushing Barclays US S&P 500 TR MSCI US REIT Natural Gas Crude Oil Spot Barclays U.S. Corporate Index Gross TR Spot Price Price Treasury 7-10 Y High Yield 2007 0.42 0.33 -0.20 0.26 -0.16 0.27 2008 0.76 0.45 0.15 0.50
-0.21 0.64 2009 0.72 0.45 0.16 0.31 -0.42 0.66 2010 0.68 0.59 0.18 0.69 -0.30 0.67 2011 0.68 0.69 0.36 0.59 -0.34 0.44 2012 067. 057. 024. 051. -038. 052. 1-Year 0.64 0.64 0.29 0.58 -0.30 0.47 2-Year 0.66 0.58 0.18 0.60 -0.33 0.54 5-Year 0.70 0.46
0.12 0.46 -0.28 0.62 Source: Bloomberg, 9/6/2007–12/31/2012, based on weekly data. Correlation is the term used to describe the historical statistical relationship between two or more quantities or variables. Perfectly correlated assets
iPath ® BARCLAYS Direct MLP Investment ETNs ETFs and Mutual Funds Return deviations
from None Investor fee; may be subject to tax at Management Fee, Tracking error direct MLP investment earlier times and higher rates than a & tax reductions direct MLP investment Liquidity Intraday on exchange Intraday on exchange ETF: Intraday
on exchange Mutual Funds: daily creation Legal structure Partnership Debt security C corporation Main risks Market risk Credit and market risk; tax treatment Market risk; tax treatment is is uncertain uncertain Source: Bloomberg 1/4/2011 –
12/31/2012. Average MLP ETF / Mutual Funds performance is the calculated market cap weighted average of MLP ETFs / Mutual Funds outstanding for each month Index returns are for illustrative purposes only. Index performance returns do not reflect any
investor fees, transactions costs and expenses. Indexes are unmanaged and one cannot invest directly in an Index. Past performance is not indicative of future results. Page 9 The analysis assumes full reinvestment of dividends and distributions, and
does not take into account possibly different reinvestment tax treatments. 140 S&P MLP TR Index Average MLP Mutual Fund Total Returns 130 Average MLP ETF Total Returns 120 Average MLP ETN Total Returns 110 100 90 80 1/4/2011 4/4/2011 7/4/2011
10/4/2011 1/4/2012 4/4/2012 7/4/2012 10/4/2012 MLP investment vehicles
MLP investment vehicles: anticipated tax treatment 1. Barclays Capital Inc. and its
affiliates, and Blackrock Investments LLC, and its affiliates, do not provide tax advice. Any discussion of U.S. federal income tax matters herein is provided as a matter of general information, and should not be construed to represent tax advice.
Please be advised that any discussion of U.S. tax matters contained herein (including any attachments): (i) is not intended or written to be used, and cannot be used, by you for the purpose of avoiding U.S. tax-related penalties, and (ii) was
written to support the promotion of marketing of the transactions or other matters addressed herein. You should refer to the applicable prospectus for any relevant MLP, ETN, ETF or Mutual Fund for more detailed information, and should also consult
your tax advisor prior to making any investment decision. 2. MLP ETFs and Mutual Funds are typically organized as “C corporations” for U.S. federal income tax purposes, rather than “regulated investment companies”. 3. Investors
in MLP ETNs may need to demonstrate that the “net underlying long-term capital gain” which would have been recognized upon a direct MLP investment with clear and convincing evidence; otherwise, all gain on an MLP ETN could be
recharacterized as ordinary income that is subject to an Pa Direct MLP Investment ETNs ETFs and Mutual Funds Anticipated US federal Partner in the MLP; income and Pre-paid forward contracts Shares in a corporation (which may income tax treatment at
deductions flow through to investors owe corporate-level tax) 2 investment level1 Anticipated U.S. federal Distributions are generally not Coupons taxed as ordinary income Dividends taxed as ordinary income tax treatment of immediately taxable but
reduce an dividend income to the extent of the distributions investor’s basis; however, because of ETF’s earnings and profits (which the “flow-through” nature of MLPs, may be less than the ETF’s investors are taxed on their
allocable distributions); thereafter, share of the MLP’s income (such distributions are generally not income increases basis and may be immediately taxable but reduce an less than the MLP’s distributions). investor’s basis Anticipated
U.S. federal Mix of ordinary income (to recapture Generally capital gain or loss, except Capital Gain or loss income tax certain deductions) and capital gain that long-term capital gain in excess of consequences of exit or loss what would have been
recognized with a direct MLP investment will likely be recharacterized as ordinary income and subject to an interest charge 3 Tax forms K-1, multiple state filings 1099 1099 iPath ® BARCLAYS Page 10
iPath® iMLP structure details Calculating the Value of the iMLP ETN _ ETN value
seeks to track the S&P MLP index, excluding fees _ An “accrued dividend” and an “accrued investor fee” are used to determine the coupon amount payable on each payment date, based on the distributions made by the index
consituents1 _ The accrued investor fee (equal to 0.80% per annum) is deducted on a daily basis from the closing indicative value of the ETNs. _ The coupon amount payable on each coupon payment date is calculated by deducting the accrued fees from
the accrued dividend as of the relevant coupon valuation date. Closing Indicative Value ETN current value Accrued Dividend2 Accrued Investor Fee2 Coupon Amount 1. An “index dividend” calculated on each calendar day represents the aggregate
cash value of distributions that a hypothetical person holding index constituents in proportion to the weights of the index constituents would have been entitled to receive with respect to any index constituent for those cash distributions whose
“ex-dividend date” occurs on such calendar day. 2. The accrued dividend on the initial valuation date will equal zero. The accrued dividend on any subsequent calendar day will equal (1) the accrued dividend as of the immediately preceding
calendar day plus (2) the dollar dividend value on such calendar day minus (3) the coupon adjustment dividend amount. The accrued investor fee on the initial valuation date will equal zero. The accrued investor fee on any subsequent calendar day
will equal (1) the accrued investor fee as of the immediately preceding calendar day plus (2) the daily fee value on such calendar day minus (3) the coupon adjustment fee amount on such calendar day. Because the daily fee value is calculated and
subtracted from the closing indicative value on a daily basis, the net effect of the fee accumulates over time and is subtracted at the rate of 0.80% per year. Page 11 BARCLAYS
iPath® Appendix BARCLAYS
iPath® Benchmark Index Comparison S&P MLP Index Alerian MLP Index Alerian MLP
Infrastructure Index Focus on companies in the GICS Energy Composite of the 50 most prominent energy Midstream-focused subset of the Alerian Description and gas sectors MLPs MLP Index Publically traded partnership with an MLP or Publically traded
partnership with an MLP or Publically traded partnership with an MLP or LLC structure on NYSE or NASDAQ and Eligibility earn the majority of its pro forma cash flow LLC structure on NYSE or NADAQ LLC structure on NYSE or NADAQ from the
transportation, storage, and processing of energy commodities Capped, float-adjusted, capitalization- Index Cap Modified cap-weighted index Float- adjusted cap-weighted index weighted methodology Market Cap $300 million $500 million $250 million
Requirement Liquidity 3 month average daily volume $2million 6 month average daily volume of 25 6 month ADV of 25 thousand units Requirements notional thousand units Additional Classification in either the GICS® Energy Minimum quarterly
distribution or trailing our Minimum quarterly distribution for trailing quarters. Maintained or Increased four quarters. Maintained or Increased Requirements Sector or Gas Utilities Industry distribution for one of last two quarters distribution
for one of last two quarters Number of Limit of 50 Constituents. Preferential criteria Limit of 25 Constituents. Preferential criteria No limit on number of constituents Constituents exists if over 50 MLPs meet requirement exists if over 50 MLPs
meet requirement 15% maximum limit for any one constituent; Capped weight of 9.49% for top 2 Weighting Limits 45% maximum limit collectively for all None constituents, 6.99% for 3-7, 4.74% for 8-18 constituents exceeding 4.5% individually. Index
Rebalancing Yearly Quarterly Quarterly No additions between rebalancing. No additions between rebalancing. No additions in between rebalancing. Deletions can occur between rebalancing Deletions can occur between rebalancing Deletions can occur
between rebalancing for Additions/ Deletions for corporate actions (mergers, delist, for corporate actions, (mergers, delisting or corporate actions, (mergers, delisting or bankruptcies) bankruptcies) bankruptcies) Page 13 BARCLAYS
iPath® MLP structure A General partner (GP) and one or more limited partners (LPs)
constitute the partnership _ GP manages the partnership operation, owns a share of partnership, and receives a share of distributions that is dependent on the partnership’s performance. _ LPs provide capital, receives cash distributions
generated from operations Structural benefits _ Fee-based revenues are usually specified in long term contracts and increase at or above inflation _ Most MLPs are monopolies in their region – high cost of the assets creating barriers to entry _
MLPs usually fund projects with secondary units or debt issuance - market approval required for funding Source: Factset as of 12/31/2012 0% 10% 20% 30% 40% 50% Diversified Large Cap Refined Product & CrudeOil Natural Gas - G&P Natural Gas
& NGL Pipelines Natural Gas - Storage Market Natural Gas - Compression Cap Wholesale by Distribution Marine Transportation sector Coal Exploration & Production General Partners Other Page 14 BARCLAYS
iPath® MLP investors 0% 10% 20% 30% 40% 50% 60% 2002 2003 2004 2005 2006
Institutional 2007 2008 2009 2010 Ownership 2011 2012 $350 Market Cap (bn) $300 $250 $200 $150 $100 $50 $0 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 As of 9/30/12: _ Institutions (such as MLP hedge
funds) held 47.3%1 _ Retail investors (such as high net worth individuals) held the other 52.7%1 1. Factset, 9/30/2012. Source: Factset:12/29/1995 - 12/31/2012 Page 15 BARCLAYS
iPath® Selected Risk Considerations An investment in any iPath ETNs linked to the
S&P MLP Index (the “ETNs”) involves risks. Selected risks are summarized here, but we urge you to read the more detailed explanation of risks described under “Risk Factors” in the applicable prospectus supplement and pricing
supplement. You May Lose Some or All of Your Principal: The ETNs are exposed to any decrease in the Volume Weighted Average Price (“VWAP”) level between the inception date and the applicable valuation date. Additionally, if the VWAP level
is insufficient to offset the negative effect of the investor fee and other applicable costs, you will lose some or all of your investment at maturity or upon redemption, even if the VWAP value has increased. Because the ETNs are subject to an
investor fee and any other applicable costs, the return on the ETNs will always be lower than the total return on a direct investment in the index components. The ETNs are riskier than ordinary unsecured debt securities and have no principal
protection. Credit of Barclays Bank PLC: The ETNs are unsecured debt obligations of the issuer, Barclays Bank PLC, and are not, either directly or indirectly, an obligation of or guaranteed by any third party. Any payment to be made on the ETNs,
including any payment at maturity or upon redemption, depends on the ability of Barclays Bank PLC to satisfy its obligations as they come due. As a result, the actual and perceived creditworthiness of Barclays Bank PLC will affect the market value,
if any, of the ETNs prior to maturity or redemption. In addition, in the event Barclays Bank PLC were to default on its obligations, you may not receive any amounts owed to you under the terms of the ETNs. Issuer Redemption: Barclays Bank PLC will
have the right to redeem or “call” the ETNs (in whole but not in part) at its sole discretion and without your consent on any trading day on or after the inception date until and including maturity. The Payment on the ETNs is Linked to the
VWAP Level, Not to the Closing Level of the Index and Not to the Published Intraday Indicative Value of the ETNs: Your payment at maturity or upon early redemption is linked to the performance of the VWAP level, as compared to the initial VWAP
level. Although the VWAP level is intended to track the performance of the Index, the calculation of the VWAP level is different from the calculation of the official closing level of the Index. Therefore, the payment at maturity or early redemption
of your ETNs, may be different from the payment you would receive if such payment were determined by reference to the official closing level of the Index. No Guaranteed Coupon Payments: You are not guaranteed to receive coupon payments on the ETNs.
You will receive a coupon payment on a coupon payment date only to the extent that the accrued dividend exceeds the accrued investor fee on the relevant coupon valuation date. The amount of the accrued dividend on any coupon valuation date depends
in part on the aggregate cash value of distributions that a reference holder would have been entitled to receive in respect of the index constituents prior to the relevant coupon valuation date. Market and Volatility Risk: The return on the ETNs is
linked to the performance of the VWAP level of the Index which, in turn, is linked to the performance of the master limited partnerships and other securities that are included as index constituents at any time. The prices of the index constituents
may change unpredictably and, as a result, affect the level of the Index and the value of your ETNs in unforeseeable ways. Concentration Risk: The index constituents are companies in the Energy Sector or Gas Utilities Sector, as determined by the
GICS® classification system. In addition, many of the index constituents are smaller, non-diversified businesses that are exposed to the risks associated with such businesses, including the lack of capital funding to sustain or grow businesses
and potential competition from larger, better financed and more diversified businesses. The ETNs are susceptible to general market fluctuations in the energy and gas MLP market and to volatile increases and decreases in value, as market confidence
in, and perceptions regarding the index constituents change. Your investment may therefore carry risks similar to a concentrated securities investment in one industry or sector. Page 16 BARCLAYS
iPath®
A Trading Market for the ETNs May Not Develop: Although the ETNs are listed on NYSE Arca, a trading market for the ETNs may not develop and the liquidity of the ETNs may be limited, as we
are not required to maintain any listing of the ETNs. Restrictions on the Minimum Number of ETNs and Date Restrictions for Redemptions: You must redeem at least 50,000 ETNs at one time in order to exercise your right to redeem your ETNs on any
redemption date. You may only redeem your ETNs on a redemption date if we receive a notice of redemption from you by certain dates and times as set forth in the pricing supplement. Tax Treatment: Significant aspects of the tax treatment of the ETNs
may be less favorable than a direct investment in MLPs and are uncertain. You should consult your own tax advisor about your own tax situation. Barclays Bank PLC has filed a registration statement (including a prospectus) with the SEC for the
offering to which this communication relates. Before you invest, you should read the prospectus and other documents Barclays Bank PLC has filed with the SEC for more complete information about the issuer and this offering. You may get these
documents for free by visiting www.iPathETN.com or EDGAR on the SEC website at www.sec.gov. Alternatively, Barclays Bank PLC will arrange for Barclays Capital Inc. to send you the prospectus if you request it by calling toll-free 1-877-764-7284, or
you may request a copy from any other dealer participating in the offering. BlackRock Investments, LLC assists in the promotion of the iPath ETNs. The ETNs may be sold throughout the day on the exchange through any brokerage account. Commissions may
apply and there are tax consequences in the event of sale, redemption or maturity of ETNs. Barclays Capital Inc., and its affiliates, and BlackRock Investments, LLC, and its affiliates, do not provide tax advice, and nothing contained herein should
be construed to be tax advice. Please be advised that any discussion of U.S. tax matters contained herein (including any attachments): (i) is not intended or written to be used, and cannot be used, by you for the purpose of avoiding U.S. tax-related
penalties, and (ii) was written to support the promotion of marketing of the transactions or other matters addressed herein. Accordingly, you should seek advice based on your particular circumstances from an independent tax advisor.
“S&P® is a registered trademark of Standard & Poor’s Financial Services LLC (“S&P”); Dow Jones® is a registered trademark of Dow Jones Trademark Holdings LLC (“Dow Jones”); and these trademarks have
been licensed for use by S&P Dow Jones Indices LLC. The S&P® trademark has been sublicensed for certain purposes by Barclays Bank PLC. The S&P MLP index (the “Index”) is a product of S&P Dow Jones Indices LLC and has
been licensed for use by Barclays Bank PLC. The ETNs are not sponsored, endorsed, sold or promoted by S&P Dow Jones Indices LLC, Dow Jones, S&P or any of their respective affiliates (collectively, “S&P Dow Jones Indices”).
S&P Dow Jones Indices does not make any representation or warranty, express or implied, to the owners of the ETNs or any member of the public regarding the advisability of investing in securities generally or in the ETNs particularly or the
ability of the Index to track general market performance. ©2013 Barclays Bank PLC. All rights reserved. iPath, iPath ETNs and the iPath logo are registered trademarks of Barclays Bank PLC. All other trademarks, servicemarks or registered
trademarks are the property, and used with the permission, of their respective owners. ip-0636-1212 NOT FDIC INSURED · NO BANK GUARANTEE · MAY LOSE VALUE Page 17 BARCLAYS