Patent decision

BL number
Concerning rights in
Hearing Officer
Mrs C L Davies
Decision date
16 February 2011
Person(s) or Company(s) involved
Cellartis AB
Provisions discussed
PA 1977 Paragraph 3(d) of Schedule A2, Section 14(3), Section 2
Excluded fields (refused), Novelty, Sufficiency
Related Decisions


1. The application relates to methods for obtaining a xeno-free human blastocyst-derived stem cell line (hBS). A stem cell is a cell type that can renew itself and give rise to specialized or differentiated cells. Most research has focussed on two types of stem cells, embryonic and somatic stem cells: embryonic stem cells being derived from the pre-implanted fertilized oocyte, i.e. the blastocyst, whilst somatic stem cells are present within the adult organism, e.g. in the bone marrow. The term “xeno-free” means never exposed to, directly or indirectly, material of non-human animal origin, such as cells, tissues and/or body fluids during culture. It is stated in the application that it has so far not been possible to derive and continuously culture hBS cell lines in a completely xeno-free system and in order to do so three hurdles have to be overcome. The invention is therefore concerned with the derivation of new hBS cell lines under xeno-free conditions.

2. The Hearing Officer found that Claims 1-37, to methods for propagating and maintaining xeno-free hBS cells, were unpatentable by virtue of paragraph 3(d) to Schedule A2 to the Patents Act as relating to uses of human embryos for industrial or commercial purposes: it was not possible to work the invention of claims 1-37 without the destruction of a human embryo each time. Claim 39, to the hBS cell-line SA611, was found to be patentable but was insufficiently supported in the priority documents since a deposit of the cell-line had not been made, and was therefore not entitled to either of the priority dates of 07 October 2005 or 11 October 2005. This claim, and also claims 40-45 (when appended to claim 39) was thereby anticipated by Stem Cells, Vol.24, 2006, Ellerström, C. et al., “Derivation of a xeno-free human embryonic stem cell line”, pp.2170-2176. Claim 38, a product-by-process claim to a xeno-free hBS cell-line obtained by the method of claim 1 was considered not to be fully supported: only a cell-line defined by the markers provided, or made by the method of claim 1, had full support. This claim, together with claims 40-45 (when appended to claim 38) and 46-53 was therefore anticipated by WO 2006/029198 which provides a sialic acid Neu5Gc negative embryonic stem cell-line having markers characteristic of human embryonic stem cells. If the hBS cells of claim 38 were allowed to be characterized by the method of their production this claim would fall as unpatentable in a similar way to claim 1. The Hearing Officer therefore refused the application under 18(3) for failing to comply with paragraph 3(d) to Schedule A2, section 14(3) and section 2 of the Patents Act 1977.

Full decision O/050/11 PDF document72Kb