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Writer's pictureChetan Chadha

Untangling the Patent Thickets


PRELIMINARY OBSERVATIONS

“Thickets please …”[i]

In 1856, a group of firms jointly acquired a dominant position in sewing machine’s patents and formed the first patent pool in the world, which lasted till 1877.[ii] Around the same time, a company by the name of Draper acquired a commanding patent position for loom temples as well and ergo, began a long-term practice employing aggressive use of patent thickets.[iii] Organizations thereon have formed multiple patent thickets in the last 150 years.[iv] Such a strategy of “mutual non-aggression” became quite common in the semiconductor and computer industries[v] and led to software companies obtaining a number of “defensive” patents.[vi] Despite that, it was in the 1970s that the term “patent thicket” originated, when Xerox dominated the photocopier industry.[vii] These defensive thickets reduced research and development incentives for many new and upcoming innovators but as an advantage to those who became a part of it, reduced transactions costs and created a vertical monopoly.

The debate on the impact of patent thickets on innovation has been as old as the term itself. Yet the same has not reached at a just conclusion. Thickets create dense and overlapping set of complementary patent rights and seek to derive the strategic value from such a hold-up. The potential for patent thickets to stifle innovation depends on the extent to which the concerned organizations raise the costs for other innovators. Nevertheless, such a possibility of hold up can make thickets anti-competitive and decrease the level of innovation and competition in a particular market. Patents held by one organization impose costs on other innovators such as research and development expenditures and licensing fees paid for rights to use patented technology and in extreme set of circumstances may block inventors from accessing certain technologies.[viii]Multiple blocking patents are a result of strongly cumulative innovations, or highly complex products.[ix] Obtaining all of the necessary licenses reduces remaining profits of an innovator to an unacceptable level.[x] Prime cause for the growth of patent thickets has been the strengthening and broadening of patent rights and the growth and development in the technology and innovation sectors. People who can afford thickets aren’t worried about their cost; it’s the third parties i.e. licensee/assignees who have to pay such costs, for whom this is a cause of concern.[xi]

Through this article, we shall understand the meaning of Patent thickets, the problems that it brings with it and seek to determine the possible solutions/alternatives that could be used to eradicate this problem. There is a dearth of case law on this subject in India. Therefore, much of the discussion herein is anticipatory, placing reliance on the international scenario prevailing on this issue particularly in the United States (US) and the European Union (EU).

DEFINING PATENT THICKETS

“[T]hickets are a bit like nuclear weapons – the problem isn’t so much the fact of their existence; it’s what happens when you start using them.”[xii]

Granting a patent in itself is anti-competitive as it creates exclusivity in the form of a monopoly. Patent thickets cover a greater and establish a broader monopoly than a single patent for the individual or organization owning them. No single authoritative definition has been provided for patent thickets, rather any and all meanings attached to it have been used to describe its economic implications. The term “patent thicket” is descriptive of the difficulties that new entrants to a market may face when attempting to innovate within a technology space of inventions having existing Intellectual Property Rights.[xiii] They consist of patents that “protect components of a modular and complex technology”.[xiv] Shapiro defined a patent thicket as: “a dense web of overlapping intellectual property rights that a company must hack its way through in order to actually commercialize new technology.”[xv] He further stated, “..with cumulative innovation and multiple blocking patents, … patent rights can have the perverse effect of stifling, not encouraging, innovation.”[xvi]

Perusal of various readings on the subject suggests that the exponents/researchers of this concept have not been able to arrive at a common focal point and concrete definition.[xvii] As per the United Kingdom Intellectual Property Office, patent thickets have been broadly fragmented into the following rights:[xviii]

  1. When multiple organizations each own individual patents that are collectively necessary for a particular technology, in such cases their competing intellectual property rights form a patent thicket.

  2. Sets of overlapping property rights occurring in fragmented technology markets.

  3. When too many patents covering individual elements of a commercial product are separately owned by different entities.

Hussingger (2006) speaking in the context of patent thicket states, “A further development is that patents gained in value by their ability to be linked with other patents, which encourages patenting of marginal inventions. The resulting complex network of single patents … was given the name ‘patent thicket’.”[xix]

The academic literature on this area has highlighted a number of technology areas consisting of patent thickets such as:[xx] Semiconductors, Biotechnology, Computer Software, E-Commerce, Nanotechnology, Telecommunications and Pharmaceuticals. We shall now look at the broad scope of problems that patent thickets bring with themselves.

The Problems of Patent Thicket

“…[C]omplex web of patents which may stunts invention and discourages research and development.”[xxi]

A Negative concept: Patent thickets are used to restrict organizations and individuals to enter into a particular sphere of technology. High density of patents and aggressive patent filings has created many “no-go” areas in terms of research and development.[xxii] This prevents new inventors from accessing various technology areas.[xxiii] Thickets can also be used for strategic patenting, which involves accumulation of patents to achieve design freedom.[xxiv] Hall and Ziedonis described strategic patenting with respect to patent thickets as: “To obtain the rights to infringe patents held by external parties and to improve their leverage in negotiations with other patent owners, these firms amass large patent portfolios of their own with which to trade.”[xxv] Empirical research has suggested that thickets have a negative effect on entry into these industries.[xxvi] It stifles innovation and creativity and therefore is rightfully termed as a negative concept.

Barriers to Entry: As already reflected upon above, granting a patent in itself creates a monopoly, however the area a thicket covers may be more with a patent thicket. “The combination of complex technology and high volume patenting creates patent thickets which can be defined as dense webs of overlapping patent rights… The measures derive directly from information on blocking of one patent by another. A dense and overlapping set of complementary patent rights of which at least one patent right is blocking the production of an innovation.”[xxvii] Further, Hemphill (2003) established the view that organizations create thickets to strengthen patent rights and anticipate and prevent imitation.[xxviii] Thickets help build robust patent positions.[xxix] Patent thickets create costs for the firms whose patents make up the thicket and they also create costs for the firms who are considering future inventions. Organizations with a thicket monopoly over the market may constitute a barrier to entry into patenting, if the costs of entry or licensing of such patent rights are increased to a great degree.

Patent Assertion Entities (PAEs) or “Patent trolls”: PAEs are companies that do not actually produce a tangible product or service. It is believed that such companies merely pretend to be trading in secondary markets of patents that others have filed for, while their main intention is to sue large multinationals for exponentially large amounts of money.[xxx] The actions taken by PAEs are in no way illegal or beyond the scope of vested intellectual property rights in patents. There has been an increase in the United States in the number of patent infringement cases by PAEs, with high profiles cases such as NTP vs. RIM or Eolas vs. Microsoft being the prime examples of the same.[xxxi] This has had a negative effect on innovation.

SOLUTIONS

“We need to invent ourselves out of this mess.”[xxxii]

Patent Pools: Patent pools have always been considered as the best fit to tackle the potential for anti-competitiveness.[xxxiii] They basically involve, “an agreement between two or more patent owners to pool their patents and license amongst themselves or to a third party on pre-determined licensing terms.”[xxxiv] For the last 150 years, organizations have constructed multiple patent pools for collectively acquiring patent rights.[xxxv] America saw its first patent pool for sewing machines in the 1850s, when no one person could manage to come up with the complete sewing machine and as such the use of multiple patents became essential. This resulted in the creation of the “Sewing Machine Combination”, where the individuals pooled their patents.[xxxvi] The DVD pools between Philips & Sony and Hitachi, Matushita, Mitusbishi, Time Warner, Toshiba and JVC in the 90s is also another example of strong patent pools and their impact.[xxxvii]

For a patent pool to be successful, the pool has to be pro-competitive.[xxxviii] They have been considered as the perfect countering tool to patent thickets, especially in developing countries, particularly, in the fields of pharmaceuticals, biotechnology, nanotechnology and clean energy technologies etc.[xxxix] For patent pools to be effective, “all patents can be licensed at a single price.”[xl]

The problems, if any, have only been from an antitrust standpoint, but a pool in itself has pro-competitive benefits. They do come with their own share of risks, which apart from fostering monopoly and limiting competition, involve a much more serious threat in the form of a cartel.[xli] A cartel is an agreement between organizations at the same stage of the supply chain, used to fix prices, allocate customers or territories, restrict outputs or rig bids.[xlii] This is the reason why in most of the jurisdictions, a Cartel is considered anti-competitive and is severely punished. As per the India Competition Act, 2002, a cartel includes “an association of producers, sellers, distributors, traders or service providers who, by agreement amongst themselves, limit, control or attempt to control the production, distribution, sale or price of, or, trade in goods or provisions of services.”[xliii] A cartel is considered as an anti-competitive agreement,[xliv] punishable with a penalty up to three times of the profits for each year of the continuance of such agreement or ten percent of the average of the turnover of the cartel for preceding thee financial years, whichever is higher.[xlv]

The U.S. Supreme Court in observed that a pool might be essential if technical advancement is not be blocked by threatened litigation, such interchange may promote rather than restrain competition, if patent pools are available in reasonable terms. In the USA, the entire patent pool system has been brought under one parameter, “blocking (essential) or complementary patents belong in a pool, while substitute or competing patents are to remain separate.”[xlvi]

Affordable health care has been the biggest concern for India, as new diseases require new medicines at affordable prices, which the pharmaceutical companies are not wiling to produce owing to the limited nature of the markets and the limited profit window. In such circumstances, a patent pool appears to be an achievable solution for various pharmaceutical industries that can pool together in order to reduce research & development and production costs for such pharmaceuticals thereby expanding profits and availability of pharmaceuticals as well. As the patent pools involve multiple licensing agreements, the Indian Patents Act, 1970 (hereinafter referred to as the “Act”) governs such agreements. Section 68 of the Patents Act mandates an assignment of a patent to be in writing and duly executed, Section 69 of the Act requires an assignee, mortgagee, licensee or a person otherwise to any interest in a patent, to apply to the Controller in writing for registration of his title, or, of notice of his interest in the register and Section 140 of the Act establishes certain restrictive conditions that need to be avoided in a contract or a license, which may include:[xlvii]

  1. Requiring the purchaser, lessee, or licensee to acquire from the vendor, lessor, or licensor or his nominees, or prohibiting him from acquiring or restricting in any manner or to any extent his right to acquire from any person or prohibiting him from acquiring except from the vendor, lessor, or licensor or his nominees any article other than the patented article or an article other than that made by the patented process; or

  2. Prohibiting the purchaser, lessee or licensee from using or restricting in any manner or to any extent the right of the purchaser, lessee or licensee, to use an article other than the patented article or an article other than that made by the patented process, which is not supplied by the vendor, lessor or licensor or his nominee; or

  3. Prohibiting the purchaser, lessee or licensee from using or restricting in any manner or to any extent the right of the purchaser, lessee or licensee to use any process other than the patented process,

  4. Providing exclusive grant back, prevention to challenges to validity of Patent & Coercive package licensing, and any such condition shall be void.

In furtherance to the above, while Section 84 of the Act allows compulsory licensing of certain goods on a number of stated conditions. Section 102 of the Act vests the power with the central government to acquire a patent for public purposes. The Act and the Competition Act therefore consist provisions that may take care of situations and problems, which arise out of patent pools. With India’s stringent regimes against anti-competitive practices in place, keeping patent pools are a system of checks and balances, the pools in India may thus hold out as an alternative IP strategy to thicketed patent landscape in many crucial sectors.

Review of the renewal fees charged: Patent thickets act as barriers to entry only when the prospective social benefits of the factors giving rise to thickets outweigh the social costs induced by lower entry rates. In a hypothetical scenario, if the renewal charges for one company entering into multiple patent protection are exponentially increased, this would result in exponentially increasing the transactions cost for patent protection and as a result, may create doubts in the minds of organizations looking for blocking and creating monopoly in markets.

Role of Courts: India has many landmark judgments on Patent law in general; wherein the Courts have taken stringent measures to accord protection to intellectual property rights of individuals. However, the adjudication on patent pool/ thickets disputes is barely minimal. Prime reason for the same could be non-understanding or lack of knowledge about this concept in the country. However, in the future if such a need arises, involving PAEs and patent trolls into litigation may enable reduction in the prevalence of patenting strategies overall and in turn may limit patent densities and potential thickets.[xlviii] The high costs of litigation, enacting legislations imposing high level of damages, employing specialists to determine inventive step and lack of obviousness in an invention, shall discourage many trolls from infringing with patent rights of multinational corporations.

It is evidently clear that in the manner the Courts interpret patent claims and the extent to which they are willing to provide injunctions play an important role in creating incentives for firms to pursue aggressive legal strategies.[xlix] The courts have to act to stern the tide of litigation in high technology markets and ensure that a party establishes a right to relief effectively and beyond any cavil.

Stringent conditions for grant of patent: Patent system was devised to inspire innovation and creativity, while getting a monopoly for a limited time in return. However, the ordeal of issuing patents too easily for trivial ideas has made the patent system discouraging for breakthrough innovations and ideas.[l] The Registrar of patents must remember that the patents are to be granted particularly on the basis of a condition that it should not be obvious to those skilled in the art. Companies should not be allowed Patent protection merely for killing their competition. This requires enacting stringent requirements for granting patents and in addition to that strict monitoring and screening of patent applications, understanding inventions and granting patents only when it satisfies all the necessary conditions of the Act. The bar for patent applications needs to be higher than what it is presently. Inviting third-party comments and expert consultations and making the patent filing public may help in better execution of patent applications.[li]

International Treaties on Patents: Businesses have always and will always need freedom to operate. Instead of applying for ten patents according protection in separate countries, the patent applicants would be much more benefited if they are able to apply for just one patent globally, which comes at a higher fees. It would help them reduce their transaction costs and realize the enhanced economic value of patents. The World Intellectual Property Organization (WIPO) administers various patent-related treaties such as: Patent Cooperation Treaty and Budapest Treaty, which act as international systems for filing and deposits of patents.[lii] These treaties offer significant advantage to long-term success of an organization. Further by getting patent rights in other countries, organizations may be able to establish licensing agreements with international corporations.

Cross licensing: Cross licensing is another strategy to tackle patent thickets. They are the preferred means to escape blocked patent positions.[liii] Two organizations may cross license their patents and provide each other the freedom to operate on the technology patented by the other. Cross licensing agreements that license future inventions, as well as current portfolios reduce transaction costs.[liv] Examples include: Intel entering into many broad cross licenses with other companies such as IBM, agreements between Microsoft and JVC, which came into effect in 2008, agreement between Hewlett-Packard and Xerox, to settle their outstanding patent disputes.[lv] The traditional concerns regarding cross licensing have been elevation of prices and formation of a cartel and stringent competition laws restrains creation of such formations. Another concern with cross licenses comes in the form of lack of incentive to innovate as organizations run under the constant fear of their rival imitating their improvements. However, empirical support for this concept is evidence of the fact that such cross licenses promote rather than stifle innovation.[lvi] When IBM and Intel sign a forward looking cross license, both of them must have ensured that they incorporate clauses in such agreements that enable each one of them to innovate more freely. Policies such as IP for IP, essential patents patentability are some examples that encourage large companies to enter into bilateral agreements to break thickets and the accompanying monopoly.

INTERNATIONAL SCENARIO

United States of America (USA)

The number of pending patent applications in the USA has increased from 270,000 to over 1.1 million.[lvii] Prime reason for this has been increased patent trolling and doubling of patent infringement lawsuits, which have accounted for almost nine-tenths of that increase.[lviii] The litigation risk in the USA is much higher in pharmaceuticals and other technologies such as biotechnology, wherein it was roughly estimated that there was a likelihood of six cases per hundred patents in biotechnology.[lix] This has resulted in various organizations getting increasingly confronted with serious challenges when trying to develop and commercialize technology in the presence of patent thickets.[lx] This has also resulted in an increase in the post-grant opposition, which hasn’t been very effective in breaking the patent thickets and its effects due to low patent protection. Much hope is being derived from the America Invents Act, 2011, which has created scope of collective activity and is considered as a means to keep weak patents off the register.[lxi]

United Kingdom (UK)

There has been a steady growth in the number of international patent applications in the UK, yet in contrast to the USA there hasn’t been any significant increase in the number of cases involving patent thickets in the UK.[lxii] There is a lack of evidence in prior empirical evidence on the impact of patent thickets on the UK organizations.[lxiii] However, the uncertainty generated by patent thickets is driven as much by patents that are granted as those that are pending. The problem has been seen in the computer technology sector and is slowly emerging to be one that may disproportionately affect smaller businesses.[lxiv] It was Ian Hargreaves who in his Report in May 2011 called Digital Opportunity (A Review of Intellectual Property and Growth) had understood the problem and the impact it may cause in the form of obstructing entry to some markets and impeding innovation and recommended the following:

  • “Take a leading role in promoting international efforts to cut backlogs and manage the boom in patent applications by further extending “work sharing” with patent offices in other countries;

• Work to ensure patents are not extended into sectors, such as non-technical computer programs and business methods, which they do not currently cover, without clear evidence of benefit;

• Investigate ways of limiting adverse consequences of patent thickets, including by working with international partners to establish a patent fee structure set by reference to innovation and growth goals rather than solely by reference to patent office running costs. The structure of patent renewal fees might be adjusted to encourage patentees to assess more carefully the value of maintaining lower value patents, so reducing the density of patent thickets.”[lxv]

It is still to be seen how the government is able to incorporate these changes into the legislations and established procedures of filing patent applications across the country.

CONCLUSION

“A dense web of patents with overlapping claims that are held by several (competing) companies.”[lxvi]

Thickets are driven by multitude of reasons, which mainly include increase in the number of patent filings, reductions in patent quality, increase in technological complexity and interdependence of technological components.;[lxvii] The theoretical analysis and the qualitative evidence suggest that thickets impose significant costs on organizations.[lxviii] Radical simplifications offered above may positively impact innovation and economic growth by simplifying and speeding up the patent granting process and help in reduction of litigation. The discussion above leads to the conclusion that the operation of the patent system even though favours the patentee but could still use some more improvement. However, legislation should ensure that the Patent system promotes innovation rather than putting brakes on it. Stringent regulation of thickets shall ensure effective utilization of highly innovative and breakthrough inventions and further developing the technological landscape of the country and enabling functioning of patents as the key drivers of economic prosperity. With the focus of thickets on smartphones, semiconductors, nanotechnology and genetics in the modern day era, it would be interesting to see whether history repeats

[i] IPKat, ‘Gwilym and the thicket collectors, or why life isn’t as bad, and is more interesting, than one might think…’ (IPKat, 29 November 2011) < http://ipkitten.blogspot.in/2011/11/gwilym-and-thicket-collectors-or-why.html> accessed 01 March, 2015

[ii] J.Bessen, ‘Patent Thickets: Strategic Patenting of Complex Technologies’, at page 12

[iii] Ibid

[iv] G. Clarkson, ‘Objective Identification of Patent Thickets: A Network Analytic Approach’ v.3.9, at 2.

[v] Id 2 at page 1

[vi] Ibid

[vii] SCM Corp. v. Xerox Corp., 645 F.2d 1195 (2d Cir.1981); In re Xerox Corp., 86 F.T.C. 364 (1975).

[viii] I.M. Cockburn, M.J. MacGarvie and E. Muller ‘Patent Thickets, Licensing and Innovative Performance’ Discussion Paper No.08-101 (ZEW Discussion Paper, October 29, 2009), at 2 <ftp://ftp.zew.de/pub/zew-docs/dp/dp08101.pdf > accessed on 01 March 2016

[ix] Ibid

[x] Id at 3.

[xi] IPKat, ‘It’s not just copyright: further thoughts on the UK government’s further thoughts’ (IPKat, 04 August, 2011) < http://ipkitten.blogspot.in/2011/08/its-not-just-copyright-further-thoughts.html> accessed on 01 March 2016

[xii] Ibid

[xiii] IPO, ‘Patent thickets, an overview subject to peer review’ (IPO, 25 November 2011) at (iii) <https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/312540/informatic-thickets.pdf> accessed 01 March, 2016

[xiv] B. Hall, C. Helmers, G.V. Graevenitz, C. R. – Bondibene, ‘A Study of Patent Thickets’ (UKIPO, October 29, 2012), at 2

[xv] G. Clarkson, ‘Objective Identification of Patent Thickets: A Network Analytic Approach’ v.3.9, at 2.

[xvi] Ibid.

[xvii] Id 13, at 3

[xviii] Ibid.

[xix] E.J. Egan & D.J.Teece,’Untangling the Patent Thicket Literature’ (Tusher Center for Management of Intellectual Capital, July 2015) at 16.

[xx] Id 13, at 4

[xxi] Andrew Gowers, ‘Andrew Gowers Quotes’

< http://www.worldofquotes.com/author/Andrew+Gowers/1/index.html > accessed April 12, 2016

[xxii] Id 13, at 6

[xxiii] Id 13, at 6

[xxiv] Id 19, at 13

[xxv] Ibid

[xxvi] S.Wagner, ‘Are ‘Patent Thickets’ Smothering Innovation?’ <http://insights.som.yale.edu/insights/are-patent-thickets-smothering-innovation> accessed 06 March, 2016

[xxvii] Id 13, at 4

[xxviii] Id 19, at 15

[xxix] Ibid.

[xxx] Id 13, at 16

[xxxi] Id 14, at 19

[xxxii] Bloomberg Business, ‘Cutting Through the Patent Thicket’ (BloomberBusiness, 19 December, 2005) < http://www.bloomberg.com/bw/stories/2005-12-19/cutting-through-the-patent-thicket> accessed 03 March 2016

[xxxiii] Id 13, at 11

[xxxiv] I Barpujari, ‘Facilitating Access or Monopoly: Patent Pools at the Interface of Patent and Competition Regimes’ (Journal of Intellectual Property Rights, Vol.15 September 2010, pp 345-346),

[xxxv] Id 15, at 2.

[xxxvi] Id 13, at 9

[xxxvii] Id 34, at 347

[xxxviii] Ibid, at 22 and 23

[xxxix] Id 34, at 345

[xl] Id 34, at 346

[xli] Id 34, at 348

[xlii] Ibid

[xliii] Section 2 (c) Competition Act, 2002 <http://www.cci.gov.in/sites/default/files/cci_pdf/competitionact2012.pdf> accessed on 04 March, 2016

[xliv] Section 3(3), Ibid

[xlv] Section 27(b), Ibid

[xlvi] Id 34, at 350

[xlvii] Section 140 (1) (iii) of the Patents Act, 1970 <http://ipindia.nic.in/ipr/patent/patent_Act_1970_28012013_book.pdf> accessed 04 March 2016

[xlviii] Id 13, at 18

[xlix] Id 14, at 14

[l] Id 25

[li] Id 25

[lii] WIPO, ‘Patent-related Treaties administered by WIPO’ available at < http://www.wipo.int/patent-law/en/treaties.html> accessed March 7, 2016

[liii] C Shapiro, ‘Navigating the Patent Thicket: Cross licenses, Patent Pools and Standard Setting in [Innovation Policy and the Economy]’ (MIT Press, January 2001), at page 129

[liv] Id 19, at 18

[lv] Id 53, at 130

[lvi] Ibid

[lvii] J. Pethokoukis, ‘How the US patent system is strangling US innovation’ (American Enterprise Institute, November 24, 2014), < https://www.aei.org/publication/us-patent-system-strangling-us-innovation/> accessed 03 March, 2016

[lviii] Ibid

[lix] D. Harhoff, G.v. Graevenitz, S.Wagner ‘Conflict Resolution, Public Goods and Patent Thickets’, (May 3rd, 2014) at Page 7 <https://portal.uc3m.es/portal/page/portal/dpto_economia_empresa/seminarios/seminarios_externos_2014_2015/082E13C063A544D2E05075A36FB0584C > accessed 04 March, 2016

[lx] Ibid, at 18

[lxi] Id 31, at 19

[lxii] Id 14, at 24

[lxiii] Ibid, at 59

[lxiv] C Waelde, G Laurie, A Brown, S Kheria, J Cornwell ‘Contemporary Intellectual Property’, at 392 <https://books.google.co.in/books?id=PaicAQAAQBAJ&pg=PA392&lpg=PA392&dq=patent+thickets+in+the+UK&source=bl&ots=fr87_WE9n3&sig=ylXXdIuwoCALQGVW15X5b0KXD3A&hl=en&sa=X&ved=0ahUKEwiblsfIgK7LAhWDv44KHSOZDHIQ6AEIWDAI#v=onepage&q=patent%20thickets%20in%20the%20UK&f=false> accessed 05 March, 2016

[lxv] At Page 9, <https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/32563/ipreview-finalreport.pdf> accessed 05 March, 2016

[lxvi] Id 10, at 51

[lxvii] B.H. Hall, C. Helmers, G.V. Graevenitz, ‘Technology Entry in the Presence of Patent Thickets’ (IFS Working Paper, January 16, 2016) at page 19 <http://www.ifs.org.uk/uploads/publications/wps/wp201602.pdf> accessed 06 March, 2016

[lxviii] Ibid


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