Picture of William Jean-Baptiste

William Jean-Baptiste

Head of Tax

CMS Luxembourg
Rue Goethe 3
L-1637 Luxembourg
Languages French, English

William’s practice focuses on tax structuring of transactions and on-going tax management.

He has strong track record in advising its clients on complex business transactions and matters, including acquisitions and holding structures, real estate and private equity structures, financing instruments, M&A (mergers and reorganizations of financial institutions), securitisation transactions, structured products developments and due-diligences.

Before joining CMS, William has also worked a few years as in-house counsel for Private Banks in Luxembourg focusing on wealth planning and family office services. Therefore, he has developed a sound expertise in assisting (ultra) high net worth individuals in the management of their cross-border legal and tax planning needs. 

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  • 2010 – Complementary courses in Luxembourg Law “CCDL”, Ministry of Justice, Luxembourg
  • 2006 – Master II in Business Taxation with honours, Toulouse I University Capitole, Toulouse 
  • 2005 – Master II in Asset Management and Private Banking (with concentration in taxation for individuals) with honours, Toulouse I University Capitole, Toulouse 
  • 2004 – Master I in Business Law with honours, Toulouse I University Capitole, Toulouse 
  • 2003 – Bachelor in Law, Toulouse I University Capitole, Toulouse 
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April 2018
Tax Con­nect Flash | VAT group in­tro­duced by a bill...
Brexit re­lo­ca­tions: The view from CMS France, Ger­many and Lux­em­bourg
Tax and em­ploy­ment law factors in France, Ger­many and Lux­em­bourg This art­icle sets out views from CMS law­yers in France, Ger­many and Lux­em­bourg. From the per­spect­ive of law­yers in those jur­is­dic­tions, Brexit has already seen UK-based busi­nesses move part or.
Tax Con­nect Flash | Up­date fol­low­ing the pub­lic­a­tion...
Ac­cess to AML in­form­a­tion on tax­pay­ers by Lux­em­bourg tax au­thor­it­ies
On 10 Au­gust 2018 new pro­vi­sions entered in­to force in na­tion­al law to al­low the Lux­em­bourg tax au­thor­it­ies to have ac­cess to in­form­a­tion on tax­pay­ers for anti-money laun­der­ing (“AML”) pur­poses (the “Law”).
Lux­em­bourg | Coun­try-by-Coun­try Re­port­ing
Lux­em­bourg has star­ted the MLI rat­i­fic­a­tion pro­ced­ure
On 7 June 2017 Lux­em­bourg and more than 70 oth­er jur­is­dic­tions signed the mul­ti­lat­er­al in­stru­ment (“MLI”) to in­teg­rate base erosion and profit shift­ing (“BEPS”) meas­ures in­to double tax treat­ies.
The Lux­em­bourg ATAD bill of law has been pub­lished
Coun­cil Dir­ect­ive (EU) 2016/1164, the “Anti Tax Avoid­ance Dir­ect­ive” or «ATAD 1 » pub­lished on 12 Ju­ly 2016, im­ple­ments the OECD’s re­com­mend­a­tions set out in the Base Erosion and Profit Shift­ing (“BEPS”).
Trans­fer pri­cing: new re­quire­ments in 2017 tax re­turns
The Lux­em­bourg Tax Au­thor­it­ies (“LTA”) in­ser­ted in Form 500 “Cor­por­ate in­come tax, mu­ni­cip­al busi­ness and net worth tax re­turn for res­id­ent cor­por­a­tions” for the tax re­turn 2017 the fol­low­ing new dis­clos­ure re­quire­ments: Is the com­pany is en­gaged in trans­ac­tions.
Ad­di­tion­al trans­par­ency ob­lig­a­tions for Lux­em­bourg tax­pay­ers: de­fens­ive...
On 7 May, 2018, the Lux­em­bourg tax au­thor­it­ies is­sued a new cir­cu­lar “Cir­cu­lar LG – A n. 64 re­lat­ing to the de­fens­ive meas­ures in re­la­tion to the EU list of non-co­oper­at­ive jur­is­dic­tions for tax pur­poses” (the Cir­cu­lar).
A new IP re­gime in Lux­em­bourg
The bill of Law n°7163 im­ple­ment­ing the new tax re­gime ap­plic­able to in­tel­lec­tu­al prop­erty as­sets (the “new IP re­gime”) was ap­proved by a first con­sti­tu­tion­al vote on 22 March 2018 and should be ex­empt from the second con­sti­tu­tion­al vote.
Re­duced VAT rates: a re­form that in­creases the flex­ib­il­ity of EU Mem­ber...
Pur­su­ant to Art­icle 100 of the VAT Dir­ect­ive call­ing on the European Coun­cil to re­view the scope of re­duced VAT rates, the European Com­mis­sion pub­lished on 18 Janu­ary 2018 a pro­pos­al for a Coun­cil Dir­ect­ive amend­ing the Dir­ect­ive 2006/112/EC (the « VAT Dir­ect­ive.
Hu­man rights also ap­plies on VAT lit­ig­a­tions
The rul­ing of the Court of Justice of the European Uni­on (CJEU) of 5 Decem­ber 2017 on case C-42/17 "M. A. S. and M. B. " is re­mark­able, as it went as far as pla­cing the European Charter of Fun­da­ment­al Rights and es­pe­cially the European Con­ven­tion on Hu­man Rights.